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1.
J Cardiothorac Surg ; 19(1): 498, 2024 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-39198833

RESUMO

OBJECTIVE: This study aims to compare the perioperative outcomes and disease-free survival (DFS) between pneumonectomy after immunochemotherapy and chemotherapy. METHODS: We retrospectively identified patients who received neoadjuvant immunotherapy (n = 15) or chemotherapy alone (n = 12) in our single center between 2021 and 2023. The primary end point was 30-day major complications. The secondary end point was major pathologic response. RESULTS: There was no significant difference in operation time, blood loss and postoperative stay time between ICI (Received immune checkpoint inhibitor treatment including PD-1 and PD-L1 inhibitors) and Chemo cohort. There were also no difference in postoperative complications including complications > grade III, 90-day death and bronchial fistula. The pCR rate was 40.0% (6/15) in the ICI cohort versus 0.0% (0/12) in the chemo cohort (p = 0.020). The MPR or pCR rate was 60.0% (9/15) in the ICI cohort versus 8.3% (1/12) in the chemo cohort (p = 0.014). ICI cohort was associated with an improved overall 1, 2, and 3-year disease-free survival(DFS)compared with chemo cohort. At the same time, both patients received ICI and Chemo were grouped according to whether pCR occurred or not, and it was found that DFS in the pCR group was better than DFS in the non-pCR group. CONCLUSIONS: Based on our results, we argue that compared with pneumonectomy after isolated chemotherapy, pneumonectomy after immunochemotherapy not added 90-day mortality, postoperative, morbidity, but improved DFS; thus, it should be the induction therapy choice for anatomically eligible centrally located lung cancers.


Assuntos
Neoplasias Pulmonares , Pneumonectomia , Humanos , Masculino , Feminino , Estudos Retrospectivos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/cirurgia , Neoplasias Pulmonares/terapia , Pessoa de Meia-Idade , Idoso , Intervalo Livre de Doença , Imunoterapia/métodos , Terapia Neoadjuvante , Inibidores de Checkpoint Imunológico/uso terapêutico , Complicações Pós-Operatórias/mortalidade
2.
J Mol Model ; 29(5): 134, 2023 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-37041399

RESUMO

Magnaporthe oryzae is the causal agent of rice blast, and understanding how abiotic stress affects the resistance of plants to this disease is useful for designing disease control strategies. In this paper, the effects of temperature and microwave irradiation on the effector complex comprising APikL2A from M. oryzae and sHMA25 from foxtail millet were investigated by molecular dynamics simulations using the GROMACS software package. While the structure of APikL2A/sHMA25 remained relatively stable in a temperature range of 290 K (16.85 °C) to 320 K (46.85 °C), the concave shape of the temperature-dependent binding free energy curve indicated that there was maximum binding affinity between APikL2A and sHMA25 at 300 K-310 K. This coincided with the optimum infectivity temperature, thus suggesting that coupling of the two polypeptides may play a role in the infection process. A strong oscillating electric field destroyed the structure of APikL2A/sHMA25, although it was stable and not susceptible to weak electric fields.


Assuntos
Magnaporthe , Oryza , Temperatura , Micro-Ondas , Simulação de Dinâmica Molecular
3.
Front Surg ; 9: 934148, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36111234

RESUMO

Background: With advances in early diagnosis and treatment, the number of cancer survivors continues to grow, and more and more cancer survivors face the threat of second primary cancer (SPM). Second primary pancreatic ductal adenocarcinoma (spPDAC) is an important subclass of SPM, but its prognostic characteristics are poorly understood. Methods: A total of 5,439 spPDAC samples and 67,262 primary pancreatic ductal adenocarcinoma (pPDAC) samples were extracted from the SEER database for this study. Survival differences between spPDAC and pPDAC samples were compared using Kaplan-Meier curves and log-rank tests. The Fine and Gray proportional subdistributed hazard method was used to analyze potential associations between clinical variables and pancreatic ductal adenocarcinoma-specific death (PDACSD) and death from other causes. After that, the clinical variables significantly related to PDACSD were screened out to construct a competing risk nomogram, which was used to evaluate the probability of the occurrence of PDACSD. The C-index was used to evaluate the discriminative ability of the model. The area under the curve (AUC) was used to verify the discrimination of the model. The calibration curve was used to verify the calibration of the model. Decision curve analysis (DCA) was used to validate the clinical utility of the model. Results: Compared with patients with spPDAC, the pPDAC sample had a better prognosis (p = 0.0017). Across all spPDAC samples, the three most common sites of first-present cancer were the prostate, breast, and digestive system. Age (p < 0.001), race (p = 0.006), interval (p = 0.016), location (p < 0.001), T stage (p = 0.003), M stage (p < 0.001), chemotherapy (p < 0.001), and radiotherapy (p = 0.006) were the clinical variables associated with PDACSD screened by multivariate competing risks analysis. The concordance index values for the training and validation sets were 0.665 (95% CI, 0.655, 0.675) and 0.666 (95% CI, 0.650, 0.682), respectively. AUC, calibration curve, and DCA indicated that the model we constructed had good discrimination, calibration, and clinical utility. Conclusions: In conclusion, we first analyzed the impact of previous cancer history on prognosis. We then constructed a competing risk model that can predict the probability of developing PDACSD in spPDAC. This model has good discriminative ability, calibration, and clinical practicability and has certain guiding value for clinical decision-making.

4.
Molecules ; 27(5)2022 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-35268665

RESUMO

Wolfberry (Lycium barbarum L.) is an important economic crop widely grown in China. The effects of salt-alkaline stress on metabolites accumulation in the salt-tolerant Ningqi1 wolfberry fruits were evaluated across 12 salt-alkaline stress gradients. The soil pH, Na+, K+, Ca2+, Mg2+, and HCO3- contents decreased at a gradient across the salt-alkaline stress gradients. Based on the widely-targeted metabolomics approach, we identified 457 diverse metabolites, 53% of which were affected by salt-alkaline stress. Remarkably, soil salt-alkaline stress enhanced metabolites accumulation in wolfberry fruits. Amino acids, alkaloids, organic acids, and polyphenols contents increased proportionally across the salt-alkaline stress gradients. In contrast, nucleic acids, lipids, hydroxycinnamoyl derivatives, organic acids and derivatives and vitamins were significantly reduced by high salt-alkaline stress. A total of 13 salt-responsive metabolites represent potential biomarkers for salt-alkaline stress tolerance in wolfberry. Specifically, we found that constant reductions of lipids and chlorogenic acids; up-regulation of abscisic acid and accumulation of polyamines are essential mechanisms for salt-alkaline stress tolerance in Ningqi1. Overall, we provide for the first time some extensive metabolic insights into salt-alkaline stress tolerance and key metabolite biomarkers which may be useful for improving wolfberry tolerance to salt-alkaline stress.


Assuntos
Lycium , Tolerância ao Sal , Frutas , Metabolômica , Salinidade , Estresse Salino , Estresse Fisiológico
5.
J Neuroendocrinol ; 33(8): e13006, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34235800

RESUMO

In hungry animals, neuropeptide Y (NPY) neurones in the arcuate nucleus (ArcN) are activated to suppress energy expenditure, in part by decreasing brown adipose tissue sympathetic nerve activity (BAT SNA); however, the NPY receptor subtype and brain neurocircuitry are unclear. In the present study, we investigated the inhibition of BAT SNA by exogenous and endogenous NPY via binding to Y1 receptors (NPY1R) in the hypothalamic paraventricular nucleus (PVN) and dorsomedial hypothalamus (DMH), in anaesthetised male rats. Downstream projections of PVN/DMH NPY1R-expressing neurones were identified using male Npy1r-cre mice and localised unilateral DMH or PVN injections of an adeno-associated virus, which allows for the cre-dependent expression of a fluorescent protein (mCherry) in the cell bodies, axon fibres and nerve terminals of NPY1R-containing neurones. Nanoinjections of NPY into the DMH of cooled rats decreased BAT SNA, as well as mean arterial pressure (MAP) and heart rate (HR), and these responses were reversed by subsequent injection of the selective NPY1R antagonist, BIBO3304. In warmed rats, with little to no BAT SNA, bilateral nanoinjections of BIBO3304 into the DMH or PVN increased BAT SNA, MAP and HR. DMH NPY1R-expressing neurones projected heavily to the raphe pallidus (RPa), which houses BAT presympathetic neurones, as well as the PVN. In anaesthetised mice, DMH BIBO3304 increased splanchnic SNA, MAP and HR, all of which were reversed by nonselective blockade of the PVN with muscimol, suggesting that DMH-to-PVN connections are involved in this DMH BIBO3304 disinhibition. PVN Y1R expressing neurones also projected to the RPa, as well as to the nucleus tractus solitarius. We conclude that NPY tonically released in the DMH and PVN suppresses BAT SNA, MAP and HR via Y1R. Downstream neuropathways for BAT SNA may utilise direct projections to the RPa. Release of tonic NPY inhibition of BAT SNA may contribute to feeding- and diet-induced thermogenesis.


Assuntos
Sistema Cardiovascular/efeitos dos fármacos , Núcleo Hipotalâmico Dorsomedial/efeitos dos fármacos , Neuropeptídeo Y/farmacologia , Núcleo Hipotalâmico Paraventricular/efeitos dos fármacos , Termogênese/efeitos dos fármacos , Animais , Pressão Sanguínea/efeitos dos fármacos , Sistema Cardiovascular/inervação , Núcleo Hipotalâmico Dorsomedial/metabolismo , Frequência Cardíaca/efeitos dos fármacos , Masculino , Camundongos , Camundongos Transgênicos , Núcleo Hipotalâmico Paraventricular/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores de Neuropeptídeo Y/metabolismo , Receptores de Neuropeptídeo Y/fisiologia , Sistema Nervoso Simpático/efeitos dos fármacos , Sistema Nervoso Simpático/metabolismo
6.
Commun Biol ; 4(1): 671, 2021 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-34083720

RESUMO

Wolfberry Lycium, an economically important genus of the Solanaceae family, contains approximately 80 species and shows a fragmented distribution pattern among the Northern and Southern Hemispheres. Although several herbaceous species of Solanaceae have been subjected to genome sequencing, thus far, no genome sequences of woody representatives have been available. Here, we sequenced the genomes of 13 perennial woody species of Lycium, with a focus on Lycium barbarum. Integration with other genomes provides clear evidence supporting a whole-genome triplication (WGT) event shared by all hitherto sequenced solanaceous plants, which occurred shortly after the divergence of Solanaceae and Convolvulaceae. We identified new gene families and gene family expansions and contractions that first appeared in Solanaceae. Based on the identification of self-incompatibility related-gene families, we inferred that hybridization hotspots are enriched for genes that might be functioning in gametophytic self-incompatibility pathways in wolfberry. Extremely low expression of LOCULE NUBER (LC) and COLORLESS NON-RIPENING (CNR) orthologous genes during Lycium fruit development and ripening processes suggests functional diversification of these two genes between Lycium and tomato. The existence of additional flowering locus C-like MADS-box genes might correlate with the perennial flowering cycle of Lycium. Differential gene expression involved in the lignin biosynthetic pathway between Lycium and tomato likely illustrates woody and herbaceous differentiation. We also provide evidence that Lycium migrated from Africa into Asia, and subsequently from Asia into North America. Our results provide functional insights into Solanaceae origins, evolution and diversification.


Assuntos
Cromossomos de Plantas/genética , Genoma de Planta/genética , Lycium/genética , Solanaceae/genética , Sequenciamento Completo do Genoma/métodos , África , Ásia , Evolução Molecular , Frutas/genética , Frutas/metabolismo , Regulação da Expressão Gênica de Plantas , Geografia , Lycium/classificação , Lycium/metabolismo , América do Norte , Filogenia , Poliploidia , Polissacarídeos/metabolismo , Solanaceae/classificação , Solanaceae/metabolismo , Especificidade da Espécie
7.
Sci Rep ; 10(1): 14656, 2020 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-32887902

RESUMO

Goji (Lycium barbarum L.) is a highly medicinal value tree species. The yield and nutritional contents of goji fruit are significant affected by fertilizer level. In this study, we analyzed the yield and nutritional contents change of goji fruit, which planted in pot (vermiculite:perlite, 1:2, v:v) in growth chamber under P0 (32.5 g/per tree), P1 (65 g/per tree), and P2 (97.5 g/per tree). Meanwhile, we utilized an integrated Ultra Performance Liquid Chromatography-Electrospray Ionization-Tandem Mass Spectrometry (UPLC-ESI-MS/MS) to analysis of the response of the metabolome in goji fruit to phosphorus level. The results show that the yield of goji fruits had strongly negative correlation with phosphorus level, especially in the third harvest time. The amino acids, flavonoids, polysaccharides, and betaine contents of goji fruits in the first harvest time had obvious correlated with the level of phosphorus level. The Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment results indicated that the impact of different phosphorus fertilizer levels on each group mainly involved the biosynthesis of flavonoids. The results provide new insights into the theoretical basis of the relationship between the nutritional contents of goji fruits and phosphorus fertilizer level.


Assuntos
Fertilizantes/análise , Frutas/química , Frutas/metabolismo , Lycium/química , Lycium/metabolismo , Metaboloma , Fósforo/metabolismo , Aminoácidos/metabolismo , Betaína/metabolismo , Cromatografia Líquida de Alta Pressão , Flavonoides/metabolismo , Metabolômica/métodos , Polissacarídeos/metabolismo , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem
8.
Biol Sex Differ ; 11(1): 10, 2020 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-32160920

RESUMO

Obesity increases sympathetic nerve activity (SNA) in men, but not women. Here, we review current evidence suggesting that sexually dimorphic sympathoexcitatory responses to leptin and insulin may contribute. More specifically, while insulin increases SNA similarly in lean males and females, this response is markedly amplified in obese males, but is abolished in obese females. In lean female rats, leptin increases a subset of sympathetic nerves only during the high estrogen proestrus reproductive phase; thus, in obese females, because reproductive cycling can become impaired, the sporadic nature of leptin-induced sympathoexcitaton could minimize its action, despite elevated leptin levels. In contrast, in males, obesity preserves or enhances the central sympathoexcitatory response to leptin, and current evidence favors leptin's contribution to the well-established increases in SNA induced by obesity in men. Leptin and insulin increase SNA via receptor binding in the hypothalamic arcuate nucleus and a neuropathway that includes arcuate neuropeptide Y (NPY) and proopiomelanocortin (POMC) projections to the paraventricular nucleus. These metabolic hormones normally suppress sympathoinhibitory NPY neurons and activate sympathoexcitatory POMC neurons. However, obesity appears to alter the ongoing activity and responsiveness of arcuate NPY and POMC neurons in a sexually dimorphic way, such that SNA increases in males but not females. We propose hypotheses to explain these sex differences and suggest areas of future research.


Assuntos
Hipotálamo/metabolismo , Insulina/metabolismo , Leptina/metabolismo , Obesidade/metabolismo , Caracteres Sexuais , Sistema Nervoso Simpático/metabolismo , Animais , Feminino , Humanos , Insulina/fisiologia , Masculino , Neurônios/metabolismo , Neuropeptídeo Y/metabolismo , Pró-Opiomelanocortina/metabolismo
9.
J Physiol ; 597(15): 4087-4100, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31209877

RESUMO

KEY POINTS: Pregnancy increases sympathetic nerve activity (SNA), although the mechanisms responsible for this remain unknown. We tested whether insulin or leptin, two sympathoexcitatory hormones increased during pregnancy, contribute to this. Transport of insulin across the blood-brain barrier in some brain regions, and into the cerebrospinal fluid (CSF), was increased, although brain insulin degradation was also increased. As a result, brain and CSF insulin levels were not different between pregnant and non-pregnant rats. The sympathoexcitatory responses to insulin and leptin were abolished in pregnant rats. Blockade of arcuate nucleus insulin receptors did not lower SNA in pregnant or non-pregnant rats. Collectively, these data suggest that pregnancy renders the brain resistant to the sympathoexcitatory effects of insulin and leptin, and that these hormones do not mediate pregnancy-induced sympathoexcitation. Increased muscle SNA stimulates glucose uptake. Therefore, during pregnancy, peripheral insulin resistance coupled with blunted insulin- and leptin-induced sympathoexcitation ensures adequate delivery of glucose to the fetus. ABSTRACT: Pregnancy increases basal sympathetic nerve activity (SNA), although the mechanism responsible for this remains unknown. Insulin and leptin are two sympathoexcitatory hormones that increase during pregnancy, yet, pregnancy impairs central insulin- and leptin-induced signalling. Therefore, to test whether insulin or leptin contribute to basal sympathoexcitation or, instead, whether pregnancy induces resistance to the sympathoexcitatory effects of insulin and leptin, we investigated α-chloralose anaesthetized late pregnant rats, which exhibited increases in lumbar SNA (LSNA), splanchnic SNA and heart rate (HR) compared to non-pregnant animals. In pregnant rats, transport of insulin into cerebrospinal fluid and across the blood-brain barrier in some brain regions increased, although brain insulin degradation was also increased; brain and cerebrospinal fluid insulin levels were not different between pregnant and non-pregnant rats. Although i.c.v. insulin increased LSNA and HR and baroreflex control of LSNA and HR in non-pregnant rats, these effects were abolished in pregnant rats. In parallel, pregnancy completely prevented the actions of leptin with respect to increasing lumbar, splanchnic and renal SNA, as well as baroreflex control of SNA. Blockade of insulin receptors (with S961) in the arcuate nucleus, the site of action of insulin, did not decrease LSNA in pregnant rats, despite blocking the effects of exogenous insulin. Thus, pregnancy is associated with central resistance to insulin and leptin, and these hormones are not responsible for the increased basal SNA of pregnancy. Because increases in LSNA to skeletal muscle stimulates glucose uptake, blunted insulin- and leptin-induced sympathoexcitation reinforces systemic insulin resistance, thereby increasing the delivery of glucose to the fetus.


Assuntos
Insulina/metabolismo , Leptina/metabolismo , Gravidez/metabolismo , Sistema Nervoso Simpático/fisiologia , Animais , Núcleo Arqueado do Hipotálamo/metabolismo , Barorreflexo , Feminino , Insulina/líquido cefalorraquidiano , Resistência à Insulina , Peptídeos/farmacologia , Gravidez/fisiologia , Ratos , Ratos Sprague-Dawley , Receptor de Insulina/antagonistas & inibidores , Sistema Nervoso Simpático/metabolismo
10.
Medicine (Baltimore) ; 97(27): e11305, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29979399

RESUMO

BACKGROUND: It is challenges for surgeon to position the distal locking screw of a tibia intramedullary nail. The traditional free-hand (FH) technique is related to the proficiency of surgeons and has a long learning curve. Furthermore, the radiation dose and the accuracy of screw placement should be taken into account. The new technology, the electromagnetic navigation system (ET), which is a radiation-free way to locate the position of the drill bit. The purpose of our study is to evaluate the results of the ET for distal locking screw of a tibia intramedullary nail and to compare the effects with the FH technique. METHODS: Eighty-nine cases of tibia diaphyseal fracture who needed to treat by intramedullary nails were analyzed retrospectively, and were divided into 2 groups. Patients in navigation group (n = 54) were treated with intramedullary nail using the ET for distal locking, while other 35 patients using FH technique. Intraoperative fluoroscopy exposure times, screw insertion times, and healing times were recorded. The parameter was used for comparison in 2 groups. RESULTS: The mean time of distal locking in the ET technique was significant less than that in the FH group (5.89 ±â€Š2.02 minutes vs 12.26 ±â€Š4.40 minutes) and the exposure time was reduced in ET group significantly (2.13 ±â€Š0.73 seconds vs 19.09 ±â€Š10.41 seconds). The healing time was proved to be coincident in FH group and ET group (15.34 ±â€Š2.98w vs 16.06 ±â€Š3.74w). The one-time success rate of distal locking nail operation was 100% in the navigation group, which was significantly higher than that in FH group (P < .05). CONCLUSION: Compared with the FH technique, the ET for distal locking of tibia intramedullary nail has the advantages of high efficiency and short locking time without radiation.


Assuntos
Fixação Intramedular de Fraturas/métodos , Cirurgia Assistida por Computador/métodos , Fraturas da Tíbia/cirurgia , Adulto , Pinos Ortopédicos , Parafusos Ósseos , Fenômenos Eletromagnéticos , Feminino , Fluoroscopia/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Duração da Cirurgia , Estudos Retrospectivos , Tíbia/cirurgia
11.
Medicine (Baltimore) ; 96(29): e7450, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28723755

RESUMO

BACKGROUND: Although the method has been used widely, one of the greatest challenges for intramedullary nailing is to position the distal locking screw. A new technology, the electromagnetic navigation system, is a radiation-free way to locate the position of the drill bit and provide 3-dimensional real-time feedback of location and orientation of the drill bit relative to the locking holes. The purpose of our study was to evaluate the reliability and efficiency of the free-hand technique compared to the new electromagnetic navigation system. METHODS: Fifty-four patients with femoral fracture who needed treatment with intramedullary nails were divided into 2 groups. One group including 26 patients underwent distal locking using the standard free-hand method, whereas the electromagnetic navigation system was used with the other 29 patients. Intraoperative fluoroscopy exposure times, screw insertion times, and healing times were recorded; these parameters were used for comparison between the 2 groups. RESULTS: There were 17 males and 9 females who had femoral intramedullary nails using the free-hand technique, whereas 21 males and 8 females received intramedullary nails using the electromagnetic navigation system. The mean time of distal locking was 19.5 ±â€Š6.0 minutes in the free-hand (FH) group, whereas the time was 6.1 ±â€Š1.4 minutes in the electromagnetic (ET) group. The exposure time for the FH group was 26.8 ±â€Š13.3 seconds and 2.2 ±â€Š1.1 seconds for the ET group. Healing time proved to be comparable in the FH and ET groups (16.4 ±â€Š3.7 weeks vs 15.1 ±â€Š2.8 weeks). CONCLUSION: Under the premise of achieving the same effect, the electromagnetic navigation system has the advantage of less distal locking time and less radiation dose.


Assuntos
Pinos Ortopédicos , Fraturas do Fêmur/cirurgia , Fluoroscopia , Fixação Intramedular de Fraturas , Cirurgia Assistida por Computador , Adulto , Fenômenos Eletromagnéticos , Feminino , Fraturas do Fêmur/diagnóstico por imagem , Fêmur/diagnóstico por imagem , Fêmur/cirurgia , Humanos , Masculino , Doses de Radiação , Fatores de Tempo
12.
J Physiol ; 593(7): 1633-47, 2015 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-25398524

RESUMO

Obesity and hypertension are commonly associated, and activation of the sympathetic nervous system is considered to be a major contributor, at least in part due to the central actions of leptin. However, while leptin increases sympathetic nerve activity (SNA) in males, whether leptin is equally effective in females is unknown. Here, we show that intracerebroventricular (i.c.v.) leptin increases lumbar (LSNA) and renal (RSNA) SNA and baroreflex control of LSNA and RSNA in α-chloralose anaesthetized female rats, but only during pro-oestrus. In contrast, i.c.v. leptin increased basal and baroreflex control of splanchnic SNA (SSNA) and heart rate (HR) in rats in both the pro-oestrus and dioestrus states. The effects of leptin on basal LSNA, RSNA, SSNA and HR were similar in males and pro-oestrus females; however, i.c.v. leptin increased mean arterial pressure (MAP) only in males. Leptin did not alter LSNA or HR in ovariectomized rats, but its effects were normalized with 4 days of oestrogen treatment. Bilateral nanoinjection of SHU9119 into the paraventricular nucleus of the hypothalamus (PVN), to block α-melanocyte-stimulating hormone (α-MSH) type 3 and 4 receptors, decreased LSNA in leptin-treated pro-oestrus but not dioestrus rats. Unlike leptin, i.c.v. insulin infusion increased basal and baroreflex control of LSNA and HR similarly in pro-oestrus and dioestrus rats; these responses did not differ from those in male rats. We conclude that, in female rats, leptin's stimulatory effects on SNA are differentially enhanced by oestrogen, at least in part via an increase in α-MSH activity in the PVN. These data further suggest that the actions of leptin and insulin to increase the activity of various sympathetic nerves occur via different neuronal pathways or cellular mechanisms. These results may explain the poor correlation in females of SNA with adiposity, or of MAP with leptin.


Assuntos
Barorreflexo/efeitos dos fármacos , Estrogênios/farmacologia , Rim/inervação , Leptina/farmacologia , Região Lombossacral/inervação , Nervos Esplâncnicos/efeitos dos fármacos , Animais , Barorreflexo/fisiologia , Estradiol/sangue , Estradiol/farmacologia , Estrogênios/sangue , Ciclo Estral/efeitos dos fármacos , Ciclo Estral/fisiologia , Feminino , Insulina/farmacologia , Masculino , Hormônios Estimuladores de Melanócitos/farmacologia , Ovariectomia , Núcleo Hipotalâmico Paraventricular/efeitos dos fármacos , Núcleo Hipotalâmico Paraventricular/fisiologia , Ratos Sprague-Dawley , Receptor Tipo 3 de Melanocortina/antagonistas & inibidores , Receptor Tipo 3 de Melanocortina/fisiologia , Receptor Tipo 4 de Melanocortina/antagonistas & inibidores , Receptor Tipo 4 de Melanocortina/fisiologia , Nervos Esplâncnicos/fisiologia
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