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1.
Artigo em Inglês | MEDLINE | ID: mdl-36625275

RESUMO

Summary: Postoperative (PO) complications after transsphenoidal surgery (TSS) are rare when performed in pituitary referral centers. Partial hypopituitarism is more frequent and somewhat expected. Meningitis, cerebrospinal fluid leaks, and visual deficits are unusual. Cerebrovascular complications, including cerebral vasospasm are rare, usually under-appreciated and not mentioned to the patient prior to the surgery. This is a report of a 51-year-old male with a non-functioning pituitary macroadenoma presenting with partial hypopituitarism and visual field loss. The patient was submitted to an uneventful TSS. On the first PO day, he developed a left palpebral ptosis with unequal pupils and impaired consciousness (12 points on Glasgow Coma Scale). CT scan revealed a perimesencephalic subarachnoid hemorrhage (SAH) grade 1 according to the modified Fisher scale. High-dose dexamethasone (16 mg/day) was initiated and the patient became more alert (Glasgow 14). On the fifth PO day, due to progression of the neurological deficits (left III, IV, and VI cranial nerves palsy, ataxia, dysdiadochokinesia, right dysmetria, and dysarthria), a magnetic resonance angiography was obtained and revealed a recent mesencephalic infarct without evident vasospasm. Nevertheless, nimodipine 60 mg 4/4 h was initiated. No improvement was seen after 3 days of treatment. The patient was discharged and put on rehabilitation, returning to normal gait and balance after 7 months. This, therefore, is a case of an unexpected mesencephalic infarct probably due to vasospasm induced by minor SAH. Although exceptionally rare, informing the patient about this event prior to TSS is important due to its significant neurological impact. More data are needed considering preventive treatment with nimodipine as soon as SAH is detected after TSS and whether it would improve neurological outcomes. Learning points: Whenever neurological deficits arise after transsphenoidal surgery (TSS), systemic infection, meningitis, electrolyte imbalance, and evident hemorrhage must be promptly investigated. Although rare, cerebral vasospasm (CVS) after TSS is associated with high morbidity and high mortality rates. Vigilance for vasospasm is necessary for patients undergoing TSS for pituitary adenoma, especially those with significant suprasellar extension. Informing this event to the patient prior to TSS is essential due to its significant morbidity and mortality. Post-TSS subarachnoid hemorrhage and hemiparesis may be important clues indicating CVS and infarction. There is limited evidence in the literature regarding post-TSS CVS surveillance and treatment strategies which could have an impact on clinical decisions.

2.
J Clin Endocrinol Metab ; 108(6): 1452-1463, 2023 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-36504388

RESUMO

OBJECTIVE: To explore pituitary tumors by methylome and transcriptome signatures in a heterogeneous ethnic population. METHODS: In this retrospective cross-sectional study, clinicopathological features, methylome, and transcriptome were evaluated in pituitary tumors from 77 patients (61% women, age 12-72 years) followed due to functioning (FPT: GH-secreting n = 18, ACTH-secreting n = 14) and nonfunctioning pituitary tumors (NFPT, n = 45) at Ribeirao Preto Medical School, University of São Paulo. RESULTS: Unsupervised hierarchical clustering analysis (UHCA) of methylome (n = 77) and transcriptome (n = 65 out of 77) revealed 3 clusters each: one enriched by FPT, one by NFPT, and a third by ACTH-secreting and NFPT. Comparison between each omics-derived clusters identified 3568 and 5994 differentially methylated and expressed genes, respectively, which were associated with each other, with tumor clinical presentation, and with 2017 and 2022 WHO classifications. UHCA considering 11 transcripts related to pituitary development/differentiation also supported 3 clusters: POU1F1-driven somatotroph, TBX19-driven corticotroph, and NR5A1-driven gonadotroph adenomas, with rare exceptions (NR5A1 expressed in few GH-secreting and corticotroph silent adenomas; POU1F1 in few ACTH-secreting adenomas; and TBX19 in few NFPTs). CONCLUSION: This large heterogenic ethnic Brazilian cohort confirms that integrated methylome and transcriptome signatures classify FPT and NFPT, which are associated with clinical presentation and tumor invasiveness. Moreover, the cluster NFPT/ACTH-secreting adenomas raises interest regarding tumor heterogeneity, supporting the challenge raised by the 2017 and 2022 WHO definition regarding the discrepancy, in rare cases, between clinical presentation and pituitary lineage markers. Finally, making our data publicly available enables further studies to validate genes/pathways involved in pituitary tumor pathogenesis and prognosis.


Assuntos
Adenoma Hipofisário Secretor de ACT , Adenoma , Neoplasias Hipofisárias , Humanos , Feminino , Criança , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Masculino , Neoplasias Hipofisárias/genética , Neoplasias Hipofisárias/patologia , Adenoma/genética , Adenoma/patologia , Epigenoma , Transcriptoma , Estudos Retrospectivos , Estudos Transversais , Adenoma Hipofisário Secretor de ACT/genética , Hormônio Adrenocorticotrópico/genética
3.
J Clin Endocrinol Metab ; 108(6): 1464-1474, 2023 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-36478070

RESUMO

CONTEXT: Nicotinamide nucleotide transhydrogenase (NNT) acts as an antioxidant defense mechanism. NNT mutations cause familial glucocorticoid deficiency (FGD). How impaired oxidative stress disrupts adrenal steroidogenesis remains poorly understood. OBJECTIVE: To ascertain the role played by NNT in adrenal steroidogenesis. METHODS: The genotype-phenotype association of a novel pathogenic NNT variant was evaluated in a boy with FGD. Under basal and oxidative stress (OS) induced conditions, transient cell cultures of the patient's and controls' wild-type (WT) mononuclear blood cells were used to evaluate antioxidant mechanisms and mitochondrial parameters (reactive oxygen species [ROS] production, reduced glutathione [GSH], and mitochondrial mass). Using CRISPR/Cas9, a stable NNT gene knockdown model was built in H295R adrenocortical carcinoma cells to determine the role played by NNT in mitochondrial parameters and steroidogenesis. NNT immunohistochemistry was assessed in fetal and postnatal human adrenals. RESULTS: The homozygous NNT p.G866D variant segregated with the FGD phenotype. Under basal and OS conditions, p.G866D homozygous mononuclear blood cells exhibited increased ROS production, and decreased GSH levels and mitochondrial mass than WT NNT cells. In line H295R, NNT knocked down cells presented impaired NNT protein expression, increased ROS production, decreased the mitochondrial mass, as well as the size and the density of cholesterol lipid droplets. NNT knockdown affected steroidogenic enzyme expression, impairing cortisol and aldosterone secretion. In human adrenals, NNT is abundantly expressed in the transition fetal zone and in zona fasciculata. CONCLUSION: Together, these studies demonstrate the essential role of NNT in adrenal redox homeostasis and steroidogenesis.


Assuntos
Neoplasias do Córtex Suprarrenal , NADP Trans-Hidrogenases , Masculino , Recém-Nascido , Humanos , NADP Trans-Hidrogenases/genética , NADP Trans-Hidrogenases/metabolismo , Antioxidantes , Espécies Reativas de Oxigênio/metabolismo , Mitocôndrias/metabolismo , Neoplasias do Córtex Suprarrenal/genética
4.
Horm Metab Res ; 54(4): 224-231, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35413743

RESUMO

The aim of the study was to clarify the relationship and the time of aldosterone and renin recoveries at immediate and long-term follow-up in aldosterone-producing adenoma (APA) patients who underwent adrenalectomy. Prospective and longitudinal protocol in a cohort of APA patients was followed in a single center. Among 43 patients with primary aldosteronism (PA), thirteen APA patients were enrolled in this study. Blood was collected for aldosterone, renin, potassium, creatinine, cortisol, and ACTH before and 1, 3, 5, 7, 15, 30, 60, 90, 120, 180, 270, 360 days after adrenalectomy. At diagnosis, most patients (84%) had hypokalemia and high median aldosterone levels (54.8; 24.0-103 ng/dl) that decreased to undetectable (<2.2) or very low (<3.0) levels between fifth to seventh days after surgery; then, between 3-12 months, its levels gradually increased to the lower normal range. The suppressed renin (2.3; 2.3-2.3 mU/l) became detectable between the fifteen and thirty days after surgery, remaining normal throughout the study. The aldosterone took longer than renin to recover (60 vs.15 days; p<0.002) and patients with higher aldosterone had later recovery (p=0.03). The cortisol/ACTH levels remained normal despite the presence of a post-operative hypoaldosteronism. Blood pressure and antihypertensive requirement decreased after adrenalectomy. In conclusion, our prospective study shows the borderline persistent post-operative hypoaldosteronism in the presence of early renin recovery indicating incapability of the zona glomerulosa of the remaining adrenal gland to produce aldosterone. These findings contribute to the comprehension of differences in renin and aldosterone regulation in APA patients, although both are part of the same interconnected system.


Assuntos
Adenoma , Neoplasias das Glândulas Suprarrenais , Adenoma Adrenocortical , Hiperaldosteronismo , Hipertensão , Hipoaldosteronismo , Adenoma/cirurgia , Neoplasias das Glândulas Suprarrenais/cirurgia , Adrenalectomia , Hormônio Adrenocorticotrópico , Aldosterona , Humanos , Hidrocortisona , Hiperaldosteronismo/cirurgia , Estudos Prospectivos , Renina
5.
J Clin Endocrinol Metab ; 107(3): e1106-e1116, 2022 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-34693966

RESUMO

OBJECTIVE: Insulin sensitivity evaluation by hyperinsulinemic-euglycemic clamp in nonclassical congenital adrenal hyperplasia (NC-CAH) due to 21-hydroxilase deficiency. DESIGN AND SETTING: Cross-sectional study at university hospital outpatient clinics. PATIENTS AND METHODS: NC-CAH patients (25 females, 6 males; 24 ± 10 years) subdivided into C/NC (compound heterozygous for 1 classical and 1 nonclassical allele) and NC/NC (2 nonclassical alleles) genotypes were compared to controls. RESULTS: At diagnosis, C/NC patients presented higher basal and adrenocorticotropin-stimulated 17-hydroxyprogesterone and androstenedione levels than NC/NC genotype. Patients and controls presented similar weight, body mass index, abdominal circumference, and total fat body mass. NC-CAH patients showed higher waist-to-hip ratio, lower adiponectin and lower high-density lipoprotein cholesterol levels with no changes in fasting plasma glucose, glycated hemoglobin, homeostatic model assessment for insulin resistance, leptin, interleukin 6, tumor necrosis factor alpha, C-reactive protein, and carotid-intima-media thickness. All patients had used glucocorticoid (mean time of 73 months). Among the 22 patients with successful clamp, 13 were still receiving glucocorticoid-3 patients using cortisone acetate, 9 dexamethasone, and 1 prednisone (hydrocortisone equivalent dose of 5.5mg/m²/day), while 9 patients were off glucocorticoid but had previously used (hydrocortisone equivalent dose of 5.9mg/m2/day). The NC-CAH patients presented lower Mffm than controls (31 ± 20 vs 55 ± 23µmol/min-1/kg-1, P = 0.002). The Mffm values were inversely correlated with the duration of glucocorticoid treatment (r = -0.44, P = 0.04). There was association of insulin resistance and glucocorticoid type but not with androgen levels. CONCLUSION: Using the gold standard method, the hyperinsulinemic-euglycemic clamp, insulin resistance was present in NC-CAH patients and related to prolonged use and long-acting glucocorticoid treatment. Glucocorticoid replacement and cardiometabolic risks should be monitored regularly in NC-CAH.


Assuntos
Hiperplasia Suprarrenal Congênita/complicações , Glucocorticoides/efeitos adversos , Resistência à Insulina , Adolescente , Hiperplasia Suprarrenal Congênita/tratamento farmacológico , Adulto , Fatores de Risco Cardiometabólico , Estudos Transversais , Feminino , Técnica Clamp de Glucose/estatística & dados numéricos , Humanos , Masculino , Adulto Jovem
6.
Arch. endocrinol. metab. (Online) ; 65(5): 549-561, 2021. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1345196

RESUMO

ABSTRACT Objective: Feeding restriction in rats alters the oscillators in suprachiasmatic, paraventricular, and arcuate nuclei, hypothalamic areas involved in food intake. In the present study, using the same animals and experimental protocol, we aimed to analyze if food restriction could reset clock genes ( Clock, Bmal1 ) and genes involved in lipid metabolism ( Pgc1a, Pparg, Ucp2 ) through nutrient-sensing pathways ( Sirt1, Ampk, Nampt ) in peripheral tissues. Materials and methods: Rats were grouped according to food access: Control group (CG, food ad libitum ), Restricted night-fed (RF-n, food access during 2 h at night), Restricted day-fed (RF-d, food access during 2 h in the daytime), and Day-fed (DF, food access during 12 h in the daytime). After 21 days, rats were decapitated at ZT3 (0900-1000 h), ZT11 (1700-1800 h), or ZT17 (2300-2400 h). Blood, liver, brown (BAT) and peri-epididymal (PAT) adipose tissues were collected. Plasma corticosterone and gene expression were evaluated by radioimmunoassay and qPCR, respectively. Results: In the liver, the expression pattern of Clock and Bmal1 shifted when food access was dissociated from rat nocturnal activity; this phenomenon was attenuated in adipose tissues. Daytime feeding also inverted the profile of energy-sensing and lipid metabolism-related genes in the liver, whereas calorie restriction induced a pre-feeding increased expression of these genes. In adipose tissues, Sirt1 expression was modified by daytime feeding and calorie restriction, with concomitant expression of Pgc1a , Pparg , and Ucp2 but not Ampk and Nampt . Conclusion: Feeding restriction reset clock genes and genes involved in lipid metabolism through nutrient-sensing-related genes in rat liver, brown, and peri-epididymal adipose tissues.


Assuntos
Animais , Ratos , Hipotálamo , Fígado/metabolismo , Nutrientes , Ritmo Circadiano , Metabolismo dos Lipídeos
7.
Comput Biol Med ; 124: 103966, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32860977

RESUMO

Twelve to 66% of patients with clinically non-functioning pituitary adenoma (NFPA) experience tumor recurrence 1-5 years after the first surgery. Nevertheless, there is still no recurrence prediction factor concisely established and reproduced in the literature for NFPA management. The present study evaluates the prognostic value of MRI Radiomics features combined with machine learning models to assess recurrence after the first surgery in patients with clinically non-functioning pituitary adenomas (NFPA). We carried out a retrospective study on 27 patients with NFPA, 10 patients having experienced tumor recurrence after the first surgery and 17 who did not. Preoperative 3D T1 contrast-enhanced MR images of patients were used to extract up to 255 Radiomics features from two and three-dimensional segmented regions. Additionally, gender, age at first surgery, and the presence of remnant tumor tissue were investigated to find the correlation with NFPA recurrence. Conventional statistics tests were used to evaluate whether the outcome patient groups (stable and recurrent) were different considering each feature individually. Additionally, five well-known machine-learning algorithms were used in combination with Radiomic features to classify recurrent and stable lesions. We found statistical evidence (p < 0.02) for 6 two-dimensional and 13 three-dimensional radiomic features. We achieved accuracies of up to 96.3% for 3D-feature based models and up to 92.6% accuracies for 2D-feature based models. 3D-feature based models achieved better performances using considerably fewer features when compared to 2D-feature based models. We concluded that Radiomics have the potential of NFPA recurrence prediction after the first surgery. Three-dimensional Radiomics have superior discrimination power to predict NFPA recurrence than two-dimensional radiomic features. Finally, the combination of Radiomics with machine-learning algorithms can offer computational models capable of non-invasive, unbiased, and quick assessment that might improve the prediction of NFPA recurrence.


Assuntos
Aprendizado de Máquina , Imageamento por Ressonância Magnética , Neoplasias Hipofisárias , Algoritmos , Humanos , Neoplasias Hipofisárias/diagnóstico por imagem , Estudos Retrospectivos
8.
PLoS One ; 14(10): e0223432, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31613908

RESUMO

The present study was designed to evaluate the relationship between bone traits [bone mineral density (BMD) and trabecular bone score (TBS)] and the accumulation of fat in adipose tissues [abdominal subcutaneous (SAT), visceral (VAT), marrow (MAT) and intrahepatic lipids (IHL)], as well as insulin resistance, in subjects with Cushing's disease (CD). The study included control (C = 27), paired (P = 16) and Cushing's disease (CD = 10) groups, which underwent biochemical assessment, dual X-ray absorptiometry, TBS, and magnetic resonance imaging to determine fat deposits. The CD group showed higher serum levels of glucose and insulin, as well as HOMA-IR values, but lower circulatory levels of osteocalcin, in comparison to C and P. The CD group exhibited lower L1-L4 BMD than P (P = 1.059 ± 0.141 vs CD = 0.935 ± 0.093 g/cm2, p < 0.05) (Fig 1A). The lumbar spine BMD from the C group was similar to the other groups. TBS was lower in CD than in P and C (C = 1.512±0.077 vs P = 1.405±0.150 vs CD = 1.135±0.136; p<0.05); there was also significant difference between C and P (p<0.05). MAT, VAT, and IHL were higher in CD than in C and P (p<0.05). Considering all subjects, there was a positive association between TBS with both lumbar spine BMD (R2 = 0.45; p<0.0001) and osteocalcin (R2 = 0.44; p = 0.05). TBS was negatively associated with MAT (R2 = 0.49; p = 0.01), VAT (R2 = 0.55; p<0.05), and HOMA-IR (R2 = 0.44; p<0.01). MAT was positively related with VAT (R2 = 0.44; p<0.01) and IHL (R2 = 0.41; p<0.05). In CD, insulin resistance and adipose tissue dysfunction, including high MAT, are active players in bone deterioration, as confirmed by lower lumbar spine BMD and lower TBS. Thus, our findings point to an additional component of the already well-known complex mechanisms of osteoporosis associated with hypercortisolism.


Assuntos
Tecido Adiposo/patologia , Medula Óssea/patologia , Osso e Ossos/patologia , Síndrome Metabólica/complicações , Hipersecreção Hipofisária de ACTH/complicações , Adiponectina/metabolismo , Adulto , Peso Corporal , Densidade Óssea , Osso Esponjoso/patologia , Humanos , Resistência à Insulina , Leptina/metabolismo , Modelos Lineares , Lipídeos/análise
9.
Endocr Connect ; 8(5): 579-589, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30959478

RESUMO

OBJECTIVE: To investigate the impact of early exposure to androgen excess on gonadotropin-dependent puberty (GDP) and final height (FH) of patients with androgen-secreting adrenocortical tumors (ACT) in childhood. METHODS: Retrospective cohort study. Occurrence of GDP and achievement of FH were evaluated. Central precocious puberty (CPP) and early fast puberty (EFP) were considered pubertal disorders. Patients with normal puberty and pubertal disorders were compared. RESULTS: The study included 63 patients (44F), followed in a single institution from 1975 until 2017. At diagnosis of ACT, median age was 25.8 months; duration of signs, 6 months; stature SDS, 0.5 (-3.6 to 3.9) and bone age advancement, 14.7 months (-27.9 to 85.4). To date, 37 patients developed GDP: 26 had normal puberty; one, precocious thelarche; seven, CPP and three, EFP. GnRHa effectively treated CPP/EFP. Tall stature and older age at diagnosis of ACT were associated with risk of CPP alone (RR 4.17 (95% CI 1.17-14.80)) and CPP/EFP (RR 3.0 (95% CI 1.04-8.65)). Recurrence/metastasis during follow-up were associated with risk of CPP alone (RR 4.17 (95% CI 1.17-14.80)) and CPP/EFP (RR 3.0 (95% CI 1.12-8.02)). Among the 19 patients that reached FH, stature SDS dropped from 1.4 to -0.02 since diagnosis of ACT (P = 0.01). Seventeen achieved normal FH. There was no difference in FH SDS between patients with normal puberty and pubertal disorders (P = 0.75). CONCLUSIONS: Gonadotropin-dependent pubertal disorders are common in patients with androgen-secreting ACT in childhood. FH is usually not impaired. The study reinforces the importance of close follow-up after surgery to identify and treat consequences of early exposure to androgen excess.

10.
Growth Horm IGF Res ; 41: 71-74, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29571594

RESUMO

Growth hormone (GH) and the insulin-like growth factor I (IGF-I) have cell proliferative and differentiation properties. Whether these hormones have a role in mutagenesis is unknown. Nevertheless, severe IGF-I deficiency seems to confer protection against the development of neoplasms. Here, we report five cases of adult patients with severe and congenital isolated GH deficiency (IGHD) due to the c.57+1G>A mutation in the GHRH receptor gene, who developed tumors. Four GH-naïve subjects presented skin tumors: a 42-year-old man with a fibroepithelial polyp, a 53-year-old woman and two men (59 and 56 years old) with epidermoid skin cancers. One of these died from it after three surgeries and radiotherapy. The fifth patient was a 25-year-old woman, who had intermittently received GH replacement therapy (GHRT) from age 11 to 18, who developed an ependymoma extending from the fourth ventricle to the end of the thoracic spine. She underwent three surgical procedures, without obvious evidence of tumor recurrence during the six years follow up. These observations suggest that severe IGHD does not protect completely from development of tumors.


Assuntos
Biomarcadores/metabolismo , Nanismo Hipofisário/complicações , Hormônio do Crescimento Humano/deficiência , Mutação , Neoplasias/epidemiologia , Receptores de Neuropeptídeos/genética , Receptores de Hormônios Reguladores de Hormônio Hipofisário/genética , Adolescente , Adulto , Idoso , Criança , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Neoplasias/genética , Prognóstico , Índice de Gravidade de Doença
11.
Circulation ; 134(23): 1866-1880, 2016 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-27803035

RESUMO

BACKGROUND: Inflammation is a key feature of aldosterone-induced vascular damage and dysfunction, but molecular mechanisms by which aldosterone triggers inflammation remain unclear. The NLRP3 inflammasome is a pivotal immune sensor that recognizes endogenous danger signals triggering sterile inflammation. METHODS: We analyzed vascular function and inflammatory profile of wild-type (WT), NLRP3 knockout (NLRP3-/-), caspase-1 knockout (Casp-1-/-), and interleukin-1 receptor knockout (IL-1R-/-) mice treated with vehicle or aldosterone (600 µg·kg-1·d-1 for 14 days through osmotic mini-pump) while receiving 1% saline to drink. RESULTS: Here, we show that NLRP3 inflammasome plays a central role in aldosterone-induced vascular dysfunction. Long-term infusion of aldosterone in mice resulted in elevation of plasma interleukin-1ß levels and vascular abnormalities. Mice lacking the IL-1R or the inflammasome components NLRP3 and caspase-1 were protected from aldosterone-induced vascular damage. In vitro, aldosterone stimulated NLRP3-dependent interleukin-1ß secretion by bone marrow-derived macrophages by activating nuclear factor-κB signaling and reactive oxygen species generation. Moreover, chimeric mice reconstituted with NLRP3-deficient hematopoietic cells showed that NLRP3 in immune cells mediates aldosterone-induced vascular damage. In addition, aldosterone increased the expression of NLRP3, active caspase-1, and mature interleukin-1ß in human peripheral blood mononuclear cells. Hypertensive patients with hyperaldosteronism or normal levels of aldosterone exhibited increased activity of NLRP3 inflammasome, suggesting that the effect of hyperaldosteronism on the inflammasome may be mediated through high blood pressure. CONCLUSIONS: Together, these data demonstrate that NLRP3 inflammasome, through activation of IL-1R, is critically involved in the deleterious vascular effects of aldosterone, placing NLRP3 as a potential target for therapeutic interventions in conditions with high aldosterone levels.


Assuntos
Aldosterona/farmacologia , Artérias Mesentéricas/efeitos dos fármacos , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Acetilcolina/farmacologia , Animais , Células da Medula Óssea/citologia , Transplante de Medula Óssea , Caspase 1/deficiência , Caspase 1/genética , Humanos , Molécula 1 de Adesão Intercelular/genética , Molécula 1 de Adesão Intercelular/metabolismo , Interleucina-1beta/sangue , Leucócitos Mononucleares/citologia , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Masculino , Artérias Mesentéricas/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , NF-kappa B/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/deficiência , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Nigericina/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Receptores de Interleucina-1/deficiência , Receptores de Interleucina-1/genética , Transdução de Sinais/efeitos dos fármacos , Doenças Vasculares/induzido quimicamente
12.
Oncotarget ; 7(51): 84634-84644, 2016 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-27705928

RESUMO

BACKGROUND: Overexpression of the oncogene yes-associated-protein-1 (YAP1) is associated with increased cell proliferation in human cancers. YAP1 is a potential target of the Wnt/beta-catenin pathway, which plays an important role in adrenocortical tumors (ACT). The role of YAP1 in adrenocortical tumorigenesis has not been assessed. AIMS: To evaluate YAP1 expression in normal adrenals and pediatric ACT and its association with disease outcome. To investigate the interaction between YAP1 and the Wnt/beta-catenin pathway in adrenocortical cells. RESULTS: Strong YAP1 staining was present in fetal adrenals and pediatric ACT but weak in postnatal adrenals. In pediatric ACT, YAP1 mRNA overexpression was associated with death, recurrent/metastatic disease and lower overall survival. The inhibition of the Wnt/beta-catenin pathway increased YAP1 mRNA expression. siYAP1 increased CTNNB1/beta-catenin expression and nuclear staining regardless of DLV2, moreover, it decreased cell growth and impaired cell migration. MATERIALS AND METHODS: We assessed in 42 pediatric ACT samples the YAP1 protein expression by immunohistochemistry and mRNA expression by RT-qPCR and analyzed their association with outcome. As controls, we resort 32 fetal and postnatal normal adrenals for IHC and 10 normal adrenal cortices for RT-qPCR. The interaction between YAP1 and the Wnt/beta-catenin pathway was assessed in NCI-H295 adrenocortical cells by inhibiting the TCF/beta-catenin complex and by knocking down YAP1. CONCLUSION: YAP1 overexpression is a marker of poor prognosis for pediatric patients with ACT. In adrenocortical cells, there is a close crosstalk between YAP1 and Wnt/beta-catenin. These data open the possibility of future molecular therapies targeting Hippo/YAP1 signaling to treat advanced ACT.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Neoplasias do Córtex Suprarrenal/metabolismo , Córtex Suprarrenal/metabolismo , Fosfoproteínas/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Adolescente , Neoplasias do Córtex Suprarrenal/genética , Neoplasias do Córtex Suprarrenal/mortalidade , Carcinogênese , Linhagem Celular Tumoral , Proliferação de Células , Criança , Pré-Escolar , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Lactente , Masculino , Metástase Neoplásica , Recidiva Local de Neoplasia , Fosfoproteínas/genética , Transdução de Sinais , Análise de Sobrevida , Fatores de Transcrição , Proteínas Wnt/metabolismo , Proteínas de Sinalização YAP , beta Catenina/metabolismo
13.
Clin Endocrinol (Oxf) ; 82(4): 562-9, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25056824

RESUMO

CONTEXT AND OBJECTIVE: Sonic Hedgehog (SHH) and GLI2, an obligatory mediator of SHH signal transduction, are holoprosencephaly (HPE)-associated genes essential in pituitary formation. GLI2 variants have been found in patients with congenital hypopituitarism without complex midline cerebral defects (MCD). However, data on the occurrence of SHH mutations in these patients are limited. We screened for SHH and GLI2 mutations or copy number variations (CNV) in patients with congenital hypopituitarism without MCD or with variable degrees of MCD. PATIENTS AND METHODS: Detailed data on clinical, laboratory and neuroimaging findings of 115 patients presenting with congenital hypopituitarism without MCD, septo-optic dysplasia or HPE were analysed. The SHH and GLI2 genes were directly sequenced, and the presence of gene CNV was analysed by multiplex ligation-dependent probe amplification (MLPA). RESULTS: Anterior pituitary deficiency was found in 74% and 53% of patients with SOD or HPE, respectively. Diabetes insipidus was common in patients with HPE (47%) but infrequent in patients with congenital hypopituitarism or SOD (7% and 8%, respectively). A single heterozygous nonsense SHH mutation (p.Tyr175Ter) was found in a patient presenting with hypopituitarism and alobar HPE. No other SHH mutations or CNV were found. Nine GLI2 variations (8 missense and 1 frameshift) including a homozygous and a compound heterozygous variation were found in patients with congenital hypopituitarism or SOD, but not in HPE patients. No GLI2 CNV were found. CONCLUSION: SHH mutations or copy number variations are not a common cause of congenital hypopituitarism in patients without complex midline cerebral defects. GLI2 variants are found in some patients with congenital hypopituitarism without complex midline cerebral defects or septo-optic dysplasia. However, functional analyses of these variants are needed to strengthen genotype-phenotype relationship.


Assuntos
Proteínas Hedgehog/genética , Hipopituitarismo/congênito , Hipopituitarismo/genética , Mutação , Adolescente , Adulto , Encéfalo/fisiopatologia , Criança , Pré-Escolar , Feminino , Dosagem de Genes , Estudos de Associação Genética , Variação Genética , Heterozigoto , Holoprosencefalia/genética , Humanos , Lactente , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição Kruppel-Like/metabolismo , Imageamento por Ressonância Magnética , Masculino , Mutação de Sentido Incorreto , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Fenótipo , Hipófise/metabolismo , Transdução de Sinais , Adulto Jovem , Proteína Gli2 com Dedos de Zinco
14.
J Clin Endocrinol Metab ; 99(7): E1209-16, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24712566

RESUMO

BACKGROUND: The sonic hedgehog (SHH) pathway plays a key role in rodent adrenal cortex development and is involved in tumorigenesis in several human tissues, but data in human adrenal glands are limited. OBJECTIVES: The objectives of the study were to analyze the involvement of the SHH pathway in human adrenal development and tumorigenesis and the effects of SHH inhibition on an adrenocortical tumor (ACT) cell line. PATIENTS AND METHODS: Expression of SHH pathway components was evaluated by immunohistochemistry in 51 normal adrenals (33 fetal) and 34 ACTs (23 pediatric) and by quantitative PCR in 81 ACTs (61 pediatric) and 19 controls (10 pediatric). The effects of SHH pathway inhibition on gene expression and cell viability in the NCI-H295A adrenocortical tumor cell line after cyclopamine treatment were analyzed. RESULTS: SHH pathway proteins were present in fetal and postnatal normal adrenals and showed distinct patterns of spatiotemporal expression throughout development. Adult adrenocortical carcinomas presented with higher expression of PTCH1, SMO, GLI3, and SUFU compared with normal adult adrenal cortices. Conversely, pediatric ACTs showed lower mRNA expression of SHH, PTCH1, SMO, GLI1, and GLI3 compared with normal pediatric adrenal cortices. In vitro treatment with cyclopamine resulted in decreased GLI3, SFRP1, and CTNNB1 mRNA expression and ß-catenin staining as well as decreased cell viability. CONCLUSIONS: The SHH pathway is active in human fetal and postnatal adrenals, up-regulated in adult adrenocortical carcinomas, and down-regulated in pediatric ACTs. SHH pathway antagonism impaired cell viability. The SHH pathway is deregulated in ACTs and might provide a new target therapy to be explored.


Assuntos
Neoplasias do Córtex Suprarrenal/genética , Córtex Suprarrenal/embriologia , Córtex Suprarrenal/crescimento & desenvolvimento , Carcinoma Adrenocortical/genética , Proteínas Hedgehog/genética , Córtex Suprarrenal/metabolismo , Neoplasias do Córtex Suprarrenal/metabolismo , Carcinoma Adrenocortical/metabolismo , Adulto , Estudos de Casos e Controles , Células Cultivadas , Criança , Desenvolvimento Embrionário/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Proteínas Hedgehog/metabolismo , Humanos , Recém-Nascido , Gravidez , Estudos Retrospectivos , Transdução de Sinais/genética
15.
Clin Endocrinol (Oxf) ; 81(4): 503-10, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24717047

RESUMO

CONTEXT: The role of planar cell polarity (Wnt/PCP) and calcium-dependent (Wnt/Ca) noncanonical Wnt pathways in adrenocortical tumours (ACTs) is unknown. OBJECTIVES: To investigate the gene expression of Wnt/PCP and Wnt/Ca pathways and its association with TP53 p.R337H and CTNNB1 mutations in paediatric and adult ACTs and to correlate these findings with clinical outcome. PATIENTS: Expression of noncanonical Wnt-related genes was evaluated in 91 ACTs (66 children and 25 adults) by qPCR and the expression of beta-catenin, P53 and protein effectors of Wnt/Ca (NFAT) and Wnt/PCP (JNK) by immunohistochemistry. TP53 and CTNNB1 genes were sequenced. RESULTS: TP53 p.R337H mutation frequency was higher in children (86% vs 28%), while CTNNB1 mutation was higher in adults (32% vs 6%). Mortality was higher in adults harbouring TP53 p.R337H and in children with CTNNB1 mutations. Overexpression of WNT5A, Wnt/Ca ligand, was observed in children and adults. Overexpression of MAPK8 and underexpression of PRICKLE, Wnt/PCP mediators, were observed in paediatric but not in adult cases. Cytoplasmic/nuclear beta-catenin and P53 accumulation was observed in the majority of paediatric and adult ACTs as well as NFAT and JNK. Overexpression of MAPK8 and underexpression of PRICKLE were associated with mortality in children, while overexpression of WNT5A and underexpression of PRICKLE were associated with mortality in adults. CONCLUSIONS: In our study, TP53 p.R337H and CTNNB1 mutations correlated with poor prognosis in adults and children, respectively. We demonstrate, for the first time, the activation of Wnt/PCP and Wnt/Ca noncanonical pathway genes, and their association with poor outcome in children and adults, suggesting their putative involvement in ACTs aggressiveness.


Assuntos
Neoplasias do Córtex Suprarrenal/metabolismo , Via de Sinalização Wnt/fisiologia , Adolescente , Neoplasias do Córtex Suprarrenal/genética , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Humanos , Imuno-Histoquímica , Lactente , Masculino , Pessoa de Meia-Idade , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Via de Sinalização Wnt/genética , Adulto Jovem , beta Catenina/genética , beta Catenina/metabolismo
16.
Arq. bras. endocrinol. metab ; 58(1): 53-61, 02/2014. tab, graf
Artigo em Inglês | LILACS | ID: lil-705239

RESUMO

Objective : The Brazilian population has heterogeneous ethnicity. No previous study evaluated NR3C1 polymorphisms in a Brazilian healthy population. Materials and methods : We assessed NR3C1 polymorphisms in Brazilians of Caucasian, African and Asian ancestry (n = 380). In a subgroup (n = 40), we compared the genotypes to glucocorticoid (GC) sensitivity, which was previously evaluated by plasma (PF) and salivary (SF) cortisol after dexamethasone (DEX) suppression tests, GC receptor binding affinity (K d ), and DEX-50% inhibition (IC 50 ) of concanavalin-A-stimulated mononuclear cell proliferation. p.N363S (rs6195), p.ER22/23EK (rs6189-6190), and BclI (rs41423247) allelic discrimination was performed by Real-Time PCR (Polymerase Chain Reaction). Exons 3 to 9 and exon/intron boundaries were amplified by PCR and sequenced. Results : Genotypic frequencies (%) were: rs6195 (n = 380; AA:96.6/AG:3.14/GG:0.26), rs6189-6190 (n = 264; GG:99.6/GA:0.4), rs41423247 (n = 264; CC:57.9/CG:34.1/GG:8.0), rs6188 (n = 155; GG:69.6/GT:25.7/TT:4.7), rs258751 (n = 150; CC:88.0/CT:10.7/TT:1.3), rs6196 (n = 176; TT:77.2/TC:20.4/CC:2.4), rs67300719 (n = 137; CC:99.3/CT:0.7), and rs72542757 (n = 137; CC:99.3/CG:0.7). The rs67300719 and rs72542757 were found only in Asian descendants, in whom p.N363S and p.ER22/23EK were absent. The p.ER22/23EK was observed exclusively in Caucasian descendants. Hardy-Weinberg equilibrium was observed, except in the Asian for rs6188 and rs258751, and in the African for p.N363S. The K d , IC 50 , baseline and after DEX PF or SF did not differ between genotype groups. However, the mean DEX dose that suppressed PF or SF differed among the BclI genotypes (P = 0.03). DEX dose was higher in GG- (0.7 ± 0.2 mg) compared to GC- (0.47 ± 0.2 mg) and CC-carriers (0.47 ± 0.1 mg). Conclusion : The genotypic frequencies of NR3C1 polymorphisms in Brazilians are similar to worldwide populations. Additionally, the BclI polymorphism ...


Objetivo : Este estudo avalia polimorfismos (SNPs) do NR3C1 na população brasileira, que possui origem étnica heterogênea. Materiais e métodos : SNPs do NR3C1 foram avaliados em brasileiros de ancestralidade caucasiana, africana ou japonesa (n = 380). Em um subgrupo (n = 40), os genótipos foram comparados à sensibilidade aos glicocorticoides (GC), previamente avaliada por cortisol plasmático (PF) e salivar (SF) após supressão com dexametasona (DEX), ensaio de afinidade do receptor ao GC (K d ) e inibição por DEX de 50% da proliferação de mononucleares estimulada por concanavalina-A (IC 50 ). Discriminação alélica de p.N363S (rs6195), p.ER22/23EK (rs6189-6190) e BclI (rs41423247) foi realizada por PCR em tempo real. Éxons 3 a 9 e transições éxon/íntron foram amplificados e sequenciados. Resultados : Frequências genotípicas (%) foram: rs6195 (n = 380; AA:96,6/AG:3,14/GG:0,26), rs6189-6190 (n = 264; GG:99,6/GA:0,4), rs41423247 (n = 264; CC:57,9/CG:34,1/GG:8,0), rs6188 (n = 155; GG:69,6/GT:25,7/TT:4,7), rs258751 (n = 150; CC:88,0/CT:10,7/TT:1,3), rs6196 (n = 176; TT:77,2/TC:20,4/CC:2,4), rs67300719 (n = 137; CC:99,3/CT:0,7), e rs72542757 (n = 137; CC:99,3/CG:0,7). Enquanto rs67300719 e rs72542757 foram exclusivos dos nipodescendentes, p.N363S e p.ER22/23EK estavam ausentes nesses indivíduos. p.ER22/23EK foi exclusivo dos descendentes de caucasianos. Equilíbrio de Hardy-Weinberg foi observado, exceto nos nipodescendentes para rs6188 e rs258751 e nos afrodescendentes para p.N363S. K d , IC 50 , PF ou SF basal ou após DEX foram semelhantes entre os genótipos. Entretanto, a dose média de DEX que suprimiu PF ou SF diferiu entre os genótipos BclI (P = 0,03), sendo maior nos carreadores GG (0,7 ± 0,2 mg) comparada aos GC (0,47 ± 0,2 mg) e CC (0,47 ± 0,1 mg). Conclusão : As ...


Assuntos
Adulto , Feminino , Humanos , Masculino , Adulto Jovem , População Negra/genética , Povo Asiático/genética , População Branca/genética , Erros Inatos do Metabolismo/genética , Polimorfismo Genético/efeitos dos fármacos , Receptores de Glucocorticoides/deficiência , Anti-Inflamatórios/farmacologia , Brasil/etnologia , Proliferação de Células/efeitos dos fármacos , Dexametasona/farmacologia , Frequência do Gene , Estudos de Associação Genética , Hidrocortisona/sangue , Hidrocortisona , Leucócitos Mononucleares/efeitos dos fármacos , Polimorfismo de Nucleotídeo Único , Receptores de Glucocorticoides/genética , Análise de Sequência de DNA
17.
Arq. bras. endocrinol. metab ; 56(9): 633-637, Dec. 2012. ilus, tab
Artigo em Inglês | LILACS | ID: lil-660278

RESUMO

OBJECTIVE: To estimate the pretest probability of Cushing's syndrome (CS) diagnosis by a Bayesian approach using intuitive clinical judgment. MATERIALS AND METHODS: Physicians were requested, in seven endocrinology meetings, to answer three questions: "Based on your personal expertise, after obtaining clinical history and physical examination, without using laboratorial tests, what is your probability of diagnosing Cushing's Syndrome?"; "For how long have you been practicing Endocrinology?"; and "Where do you work?". A Bayesian beta regression, using the WinBugs software was employed. RESULTS: We obtained 294 questionnaires. The mean pretest probability of CS diagnosis was 51.6% (95%CI: 48.7-54.3). The probability was directly related to experience in endocrinology, but not with the place of work. CONCLUSION: Pretest probability of CS diagnosis was estimated using a Bayesian methodology. Although pretest likelihood can be context-dependent, experience based on years of practice may help the practitioner to diagnosis CS. Arq Bras Endocrinol Metab. 2012;56(9):633-7.


OBJETIVO: Estimar a probabilidade pré-teste do diagnóstico de síndrome de Cushing (SC) por meio de julgamento clínico utilizando abordagem Bayesiana. MATERIAIS E MÉTODOS: Médicos res­ponderam a três perguntas, em sete congressos de endocrinologia. Após obtenção da história clínica/exame físico, sem exames laboratoriais, apenas com base em sua experiência pessoal, qual a probabilidade de diagnosticar SC?; Há quanto tempo você pratica endocrinologia?; Onde você trabalha? Uma regressão beta Bayesiana, utilizando o software WinBugs, foi empregada. RESULTADOS: Foram obtidos 294 questionários. A estimativa Bayesiana da probabilidade média de diagnosticar SC foi 51,6% (IC 95%: 48,7-54,3). Houve relação direta entre probabilidade de diagnosticar SC e experiência da prática endócrina, porém não com o local de trabalho. CONCLUSÃO: A probabilidade pré-teste do diagnóstico de SC foi estimada utilizando uma metodologia Bayesiana. Embora a probabilidade pré-teste possa ser dependente do contexto, a experiência de anos de prática pode auxiliar no diagnóstico intuitivo da CS. Arq Bras Endocrinol Metab. 2012;56(9):633-7.


Assuntos
Humanos , Competência Clínica , Síndrome de Cushing/diagnóstico , Endocrinologia/normas , Julgamento , Teorema de Bayes , Congressos como Assunto , Modelos Logísticos , Modelos Teóricos , Probabilidade , Inquéritos e Questionários
18.
Clinics (Sao Paulo) ; 67(6): 591-6, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22760897

RESUMO

OBJECTIVES: Idiopathic central precocious puberty and its postponement with a (gonadotropin-releasing hormone) GnRH agonist are complex conditions, the final effects of which on bone mass are difficult to define. We evaluated bone mass, body composition, and bone remodeling in two groups of girls with idiopathic central precocious puberty, namely one group that was assessed at diagnosis and a second group that was assessed three years after GnRH agonist treatment. METHODS: The precocious puberty diagnosis and precocious puberty treatment groups consisted of 12 girls matched for age and weight to corresponding control groups of 12 (CD) and 14 (CT) girls, respectively. Bone mineral density and body composition were assessed by dual X-ray absorptiometry. Lumbar spine bone mineral density was estimated after correction for bone age and the mathematical calculation of volumetric bone mineral density. CONEP: CAAE-0311.0.004.000-06. RESULTS: Lumbar spine bone mineral density was slightly increased in individuals diagnosed with precocious puberty compared with controls; however, after correction for bone age, this tendency disappeared (CD = -0.74 + 0.9 vs. precocious puberty diagnosis = -1.73 + 1.2). The bone mineral density values of girls in the precocious puberty treatment group did not differ from those observed in the CT group. CONCLUSION: There is an increase in bone mineral density in girls diagnosed with idiopathic central precocious puberty. Our data indicate that the increase in bone mineral density in girls with idiopathic central precocious puberty is insufficient to compensate for the marked advancement in bone age observed at diagnosis. GnRH agonist treatment seems to have no detrimental effect on bone mineral density.


Assuntos
Composição Corporal/fisiologia , Densidade Óssea/fisiologia , Hormônio Liberador de Gonadotropina/agonistas , Puberdade Precoce/tratamento farmacológico , Puberdade Precoce/patologia , Absorciometria de Fóton , Adolescente , Fatores Etários , Composição Corporal/efeitos dos fármacos , Índice de Massa Corporal , Densidade Óssea/efeitos dos fármacos , Estudos de Casos e Controles , Criança , Feminino , Humanos , Valores de Referência , Estatísticas não Paramétricas , Resultado do Tratamento , Adulto Jovem
19.
Arq Bras Endocrinol Metabol ; 56(4): 244-9, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22790469

RESUMO

OBJECTIVE: To evaluate the modulation of the hypothalamus-pituitary-adrenal axis (HPA) on prolactin secretion in rats after adrenalectomy (ADX). MATERIALS AND METHODS: Plasma corticosterone, ACTH, and prolactin concentrations were measured by radioimmunoassay in rats after bilateral ADX in the short- (3 hours and 1 day) and long-term (3, 7, and 14 days). RESULTS: Animals that underwent ADX showed undetectable corticosterone levels and a triphasic ACTH response with a transient increase (3h), a decrease (1d), and further increase in the long-term after ADX. Sham animals showed a marked increase in corticosterone and ACTH levels three hours after surgery, with a decrease to basal levels thereafter. Plasma prolactin levels were not changed after ADX. CONCLUSION: There are different points of equilibrium in the HPA axis after the glucocorticoid negative feedback is removed. Prolactin plasma secretion is not altered in the short or long- term after ADX, suggesting that the peptidergic neurons essential for prolactin release are not activated after ADX.


Assuntos
Adrenalectomia/métodos , Hipotálamo/fisiologia , Sistema Hipófise-Suprarrenal/fisiologia , Prolactina/metabolismo , Animais , Corticosterona/sangue , Glucocorticoides/fisiologia , Masculino , Período Pós-Operatório , Prolactina/sangue , Radioimunoensaio , Ratos , Ratos Wistar , Fatores de Tempo
20.
Arq. bras. endocrinol. metab ; 56(4): 244-249, June 2012. ilus
Artigo em Inglês | LILACS | ID: lil-640699

RESUMO

OBJECTIVE: To evaluate the modulation of the hypothalamus-pituitary-adrenal axis (HPA) on prolactin secretion in rats after adrenalectomy (ADX). MATERIALS AND METHODS: Plasma corticosterone, ACTH, and prolactin concentrations were measured by radioimmunoassay in rats after bilateral ADX in the short- (3 hours and 1day) and long-term (3, 7, and 14 days). RESULTS: Animals that underwent ADX showed undetectable corticosterone levels and a triphasic ACTH response with a transient increase (3h), a decrease (1d), and further increase in the long-term after ADX. Sham animals showed a marked increase in corticosterone and ACTH levels three hours after surgery, with a decrease to basal levels thereafter. Plasma prolactin levels were not changed after ADX. CONCLUSION: There are different points of equilibrium in the HPA axis after the glucocorticoid negative feedback is removed. Prolactin plasma secretion is not altered in the short or long- term after ADX, suggesting that the peptidergic neurons essential for prolactin release are not activated after ADX.


OBJETIVO: Avaliar a modulação do eixo hipotálamo-hipófise-adrenal (HHA) sobre a secreção de prolactina após adrenalectomia (ADX). MATERIAIS E MÉTODOS: Quantificamos por RIE corticosterona, ACTH e prolactina plasmáticos em ratos após curtos (3 horas e 1 dia) e longos (3, 7 e 14 dias) períodos de ADX bilateral. RESULTADOS: Animais ADX mostraram níveis indetectáveis de corticosterona. As concentrações plasmáticas de ACTH apresentaram resposta trifásica: aumento transitório (3h), diminuição (1d) e novo aumento após longos períodos de ADX. Animais Sham mostraram aumento de corticosterona/ACTH após três horas de cirurgia, diminuindo posteriormente aos níveis basais. As concentrações plasmáticas de prolactina não se alteraram após ADX. CONCLUSÃO: Existem diferentes pontos de equilíbrio do eixo HHA após a remoção da retroalimentação negativa exercida pelos glicocorticoides. A secreção de prolactina não se alterou após curtos/longos períodos de ADX, sugerindo que os neurônios peptidérgicos essenciais para a liberação de prolactina não estão ativados durante os diferentes períodos de ADX.


Assuntos
Animais , Masculino , Ratos , Adrenalectomia/métodos , Hipotálamo/fisiologia , Sistema Hipófise-Suprarrenal/fisiologia , Prolactina , Corticosterona/sangue , Glucocorticoides/fisiologia , Período Pós-Operatório , Prolactina/sangue , Radioimunoensaio , Ratos Wistar , Fatores de Tempo
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