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1.
J Endocrinol Invest ; 44(7): 1501-1513, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33123965

RESUMO

PURPOSE: To cope physical and/or psychological threats, the human body activates multiple processes, mediated by a close interconnection among brain, endocrine and inflammatory systems. The aim of the study was to assess the hypothalamic-pituitary-adrenal (HPA) and hypothalamic-pituitary-thyroid (HPT) axes involvement after an acute stressful event (Emilia Romagna earthquake swarm) with a big data approach. METHODS: A retrospective, observational trial was performed, collecting all biochemical examinations regarding HPA and HPT axes performed in the same laboratory the year before and the year after the earthquake swarm (20-29 May 2012). RESULTS: Comparing 2576 pre-earthquake to 3021 post-earthquake measurements, a cortisol serum level increase was observed (p < 0.001). Similar increase was evident for urinary free cortisol (p = 0.016), but not for adrenocorticotropic hormone (p = 0.222). The biochemical hypercortisolism incidence increased from 7.6 to 10.3% after earthquakes (p = 0.001). Comparing 68,456 pre-earthquake to 116,521 post-earthquake measurements, a reduction in thyroid-stimulating hormone (TSH) levels was evident (p = 0.018), together with an increase in free triiodothyronine and free thyroxine levels (p < 0.001 and p < 0.001). Moreover, a significant increase in altered TSH after earthquakes was registered considering the epicenter-nearest measurements (p < 0.001). No clinically relevant alterations were observed considering thyroid-specific autoantibodies. CONCLUSION: A long-term HPA axis activation in the inhabitants of the earthquake-affected areas was highlighted for the first time. Moreover, an increased incidence of biochemical hypercortisolism emerged after earthquakes. We confirmed a recruitment of HPT axis after stressful events, together with increased incidence of altered TSH in the. Our big data study allowed to increase knowledge about the connection between external stressors and endocrine regulation.


Assuntos
Síndrome de Cushing/epidemiologia , Terremotos , Hidrocortisona/metabolismo , Hipotálamo/patologia , Sistema Hipófise-Suprarrenal/patologia , Glândula Tireoide/patologia , Hormônios Tireóideos/metabolismo , Adulto , Big Data , Síndrome de Cushing/metabolismo , Síndrome de Cushing/patologia , Análise de Dados , Feminino , Seguimentos , Humanos , Hipotálamo/metabolismo , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Sistema Hipófise-Suprarrenal/metabolismo , Estudos Retrospectivos , Glândula Tireoide/metabolismo
2.
J Endocrinol Invest ; 40(8): 841-850, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28326509

RESUMO

PURPOSE: Liquid-chromatography tandem mass-spectrometry (LC-MS/MS) was developed in parallel to Immunoassays (IAs) and today is proposed as the "gold standard" for steroid assays. Leydig cells of men with Klinefelter syndrome (KS) are able to respond to human chorionic gonadotropin (hCG) stimulation, even if testosterone (T) production was impaired. The aim was to evaluate how results obtained by IAs and LC-MS/MS can differently impact on the outcome of a clinical research on gonadal steroidogenesis after hCG stimulation. METHODS: A longitudinal, prospective, case-control clinical trial. (clinicaltrial.gov NCT02788136) was carried out, enrolling KS men and healthy age-matched controls, stimulated by hCG administration. Serum steroids were evaluated at baseline and for 5 days after intramuscular injection of 5000 IU hCG using both IAs and LC-MS/MS. RESULTS: 13 KS patients (36 ± 9 years) not receiving T replacement therapy and 14 controls (32 ± 8 years) were enrolled. T, progesterone, cortisol, 17-hydroxy-progesterone (17OHP) and androstenedione, were significantly higher using IAs than LC-MS/MS. IAs and LC-MS/MS showed direct correlation for all five steroids, although the constant overestimation detected by IAs. Either methodology found the same 17OHP and T increasing profile after hCG stimulation, with equal areas under the curves (AUCs). CONCLUSIONS: Although a linearity between IA and LC-MS/MS is demonstrated, LC-MS/MS is more sensitive and accurate, whereas IA shows a constant overestimation of sex steroid levels. This result suggests the need of reference intervals built on the specific assay. This fundamental difference between these two methodologies opens a deep reconsideration of what is needed to improve the accuracy of steroid hormone assays.


Assuntos
Gonadotropina Coriônica/uso terapêutico , Hormônios Esteroides Gonadais/sangue , Imunoensaio/métodos , Síndrome de Klinefelter/sangue , Espectrometria de Massas em Tandem/métodos , 17-alfa-Hidroxiprogesterona/sangue , Adolescente , Adulto , Estudos de Casos e Controles , Humanos , Hidrocortisona/sangue , Síndrome de Klinefelter/tratamento farmacológico , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Progesterona/sangue , Estudos Prospectivos , Testosterona/sangue , Adulto Jovem
3.
Eur J Endocrinol ; 174(6): 801-11, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27188454

RESUMO

BACKGROUND: Men with Klinefelter syndrome (KS) show hypergonadotropic hypogonadism, but the pathogenesis of hypotestosteronemia remains unclear. Testicular steroidogenesis in KS men was evaluated over three decades ago after human chorionic gonadotropin (hCG) stimulation, but inconclusive results were obtained. Intriguingly, some recent studies show increased intratesticular testosterone concentrations in men with KS. OBJECTIVE: To analyze serum steroid profile, as a proxy of testicular steroidogenesis, after hCG stimulation in KS compared with control men. DESIGN: A prospective, longitudinal, case-control, clinical trial. METHODS: Thirteen KS patients (36±9 years) not receiving testosterone (TS) replacement therapy and 12 eugonadic controls (32±8 years) were enrolled. Serum steroids were measured by liquid chromatography-tandem mass spectrometry (LC-MS/MS) at baseline and for five consecutive days after intramuscular injection of 5000IU hCG. RESULTS: Progesterone (P), 17-hydroxyprogesterone (17OHP), TS, and estradiol (E2) showed a significant increase (P<0.001) after hCG stimulation in both groups. On the contrary, androstenedione (AS) and dehydroepiandrosterone did not increase after hCG stimulation. The 17OHP/P ratio increased in both groups (P<0.001), the TS/AS ratio (17ß-hydroxysteroid dehydrogenase type 3 (17ßHSD3) activity) did not increase after hCG in any group, and the E2/TS ratio (aromatase activity) increased significantly in both groups (P=0.009 in KS and P<0.001 in controls). Luteinizing hormone decreased after hCG in both groups (P=0.014 in KS and P<0.001 in controls), whereas follicle-stimulating hormone decreased only in control men (P<0.001). CONCLUSION: This study demonstrates for the first time using LC-MS/MS that Leydig cells of KS men are able to respond to hCG stimulation and that the first steps of steroidogenesis are fully functional. However, the TS production in KS men is impaired, possibly related to reduced hydroxysteroid deydrogenase activity due to an unfavorable intratesticular metabolic state.


Assuntos
Gonadotropina Coriônica/uso terapêutico , Síndrome de Klinefelter/tratamento farmacológico , Testículo/efeitos dos fármacos , Testosterona/sangue , 17-Hidroxiesteroide Desidrogenases/sangue , Adulto , Gonadotropina Coriônica/farmacologia , Cromatografia Líquida , Estradiol/sangue , Humanos , Síndrome de Klinefelter/sangue , Hormônio Luteinizante/sangue , Masculino , Pessoa de Meia-Idade , Progesterona/sangue , Estudos Prospectivos , Espectrometria de Massas em Tandem , Resultado do Tratamento
4.
Br J Pharmacol ; 98(1): 218-24, 1989 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-2804546

RESUMO

1. In an experimental model of haemorrhagic shock resulting in the death of all rats within 20-30 min, the intravenous (i.v.) injection of the tertiary amine cholinesterase inhibitor physostigmine (17-70 micrograms kg-1) induced a prompt, sustained and dose-dependent improvement of cardiovascular and respiratory function, with marked increase in the volume of circulating blood and survival of all treated animals, at least for the 2 h of observation. 2. Similar results were obtained with the i.v. injection of the cholinoceptor agonist oxotremorine (5-25 micrograms kg-1), while neostigmine (54 or 70 micrograms kg-1), a quaternary cholinesterase inhibitor which cannot cross the blood-brain barrier, had negligible effects. 3. The anti-shock activities of oxotremorine and physostigmine were blocked by the intracerebroventricular injection of either of the combined nicotinic and M2-muscarinic receptor antagonists gallamine and pancuronium, or of the nicotinic antagonist mecamylamine. They were also blocked by intraperitoneal injection of the adrenergic neurone blocking agent guanethidine, but they were not antagonized by either the combined M1- and M2-muscarinic receptor antagonist atropine, the M1-muscarinic receptor antagonist pirenzepine, or the M2-muscarinic receptor 4-diphenylacetoxy-N-methylpiperidine methobromide. 4. It is concluded that cholinomimetic drugs can reverse hypovolaemic shock through central activation (seemingly mediated by nicotinic receptors) of sympathetic tone, with mobilization and redistribution of the residual blood.


Assuntos
Parassimpatomiméticos/farmacologia , Choque Hemorrágico/fisiopatologia , Animais , Pressão Sanguínea/efeitos dos fármacos , Volume Sanguíneo/efeitos dos fármacos , Contagem de Eritrócitos , Feminino , Injeções Intraventriculares , Masculino , Oxotremorina/farmacologia , Parassimpatomiméticos/administração & dosagem , Fisostigmina/farmacologia , Ratos , Ratos Endogâmicos , Respiração/efeitos dos fármacos , Choque Hemorrágico/sangue
5.
Behav Neurosci ; 103(5): 1148-50, 1989 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-2803558

RESUMO

In the behavioral despair (forced swimming) test and in the tail-suspension test, long-term (30-32 days) castration significantly increased the duration of immobility in mice. Testosterone propionate (1 or 10 mg.kg-1.day sc for 4 days), although not affecting the duration of immobility in sham-operated mice, reduced the duration of immobility in castrated mice to within normal limits. Desipramine (20 mg/kg ip) decreased the duration of immobility both in sham-operated and in castrated animals. These results indicate that castration favors an inactive behavior and that testosterone, although having no "antidepressant" effect per se, is necessary for the male animal to cope normally with adverse environmental situations.


Assuntos
Transtorno Depressivo/fisiopatologia , Testículo/fisiopatologia , Testosterona/fisiologia , Afeto/fisiologia , Animais , Nível de Alerta/fisiologia , Modelos Animais de Doenças , Reação de Fuga/fisiologia , Masculino , Camundongos , Atividade Motora/fisiologia , Orquiectomia
6.
Neuropeptides ; 20(4): 233-8, 1991 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1812405

RESUMO

In anesthetized rats, massive bleeding to a severe condition of hemorrhagic shock (invariably leading to death within 30 min) was obviously associated with a dramatic decrease in tissue blood flow and with profound modifications of several blood parameters leading to metabolic acidosis: decrease in arterial and venous pH, bicarbonate and BE, decrease in arterial pCO2 and in venous pO2 and SO2, increase in arterial pO2, venous pCO2 and venous lactate. The i.v. bolus injection of protirelin tartrate (TRH-T, 4 mg/kg), which produces a prompt and sustained reversal of the shock condition, caused a rapid increase in venous pO2, pCO2 and SO2; on the other hand, arterial and venous pH, bicarbonate and BE continued to decrease--and venous lactate to increase during the first few minutes after treatment. However venous pCO2 and lactate, as well as arterial and venous pH, returned to the pre-bleeding values within 60 min after treatment. The data are in keeping with the TRH-T-induced improvement of circulatory and respiratory functions, with mobilization of the residual blood from its capillary pooling and consequent immission of acid metabolites into the blood stream.


Assuntos
Acidose/fisiopatologia , Artérias Carótidas/fisiopatologia , Fluxo Sanguíneo Regional/efeitos dos fármacos , Choque Hemorrágico/fisiopatologia , Hormônio Liberador de Tireotropina/farmacologia , Animais , Bicarbonatos/sangue , Dióxido de Carbono/sangue , Artérias Carótidas/efeitos dos fármacos , Feminino , Masculino , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/fisiopatologia , Oxigênio/sangue , Ratos , Ratos Endogâmicos , Fatores de Tempo
7.
Eur J Pharmacol ; 194(1): 7-10, 1991 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-2060593

RESUMO

The influence of putrescine on cardiac arrhythmias induced by either permanent ligature of the left anterior coronary artery or heart reperfusion following a 5-min coronary occlusion was studied in anesthetized rats. Reperfusion-induced arrhythmias were significantly prevented by the i.v. injection of 150-200 mg/kg of putrescine, the survival rate being 100% in treated animals and 40% in controls. At a dose level of 200-300 mg/kg i.v., putrescine also significantly reduced the duration of ventricular tachycardia induced by permanent coronary occlusion. These findings show that putrescine significantly reduces the consequences of cardiac ischemia and reperfusion, probably as a consequence of its multiple stabilizing effects at the membrane level.


Assuntos
Antiarrítmicos , Arritmias Cardíacas/prevenção & controle , Doença das Coronárias/complicações , Reperfusão Miocárdica , Putrescina/farmacologia , Anestesia , Animais , Arritmias Cardíacas/etiologia , Arritmias Cardíacas/fisiopatologia , Vasos Coronários/fisiologia , Masculino , Ratos , Ratos Endogâmicos
8.
Eur J Pharmacol ; 187(3): 501-6, 1990 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-1963597

RESUMO

Long-term (33-35 days) castration caused a significant increase in the duration of immobility of male and female mice in the tail suspension test (an animal model of depression), and a significant decrease in the maximum number (Bmax) of [3H]imipramine binding sites in the cerebral cortex of male mice. In the tail suspension test, gonadotropin-releasing hormone (GnRH), s.c. injected 3 times at 3-h intervals at doses of 0.2, 2 or 20 micrograms/kg, did not significantly modify the duration of immobility of castrated animals and did not reduce that of sham-operated ones, while desipramine (20 mg/kg s.c. 1 h before testing) restored immobility to normal in castrated animals and reduced it significantly in sham-operated ones. The same treatment schedule with GnRH produced an increase in the number of [3H]imipramine Bmax in cortical membranes that was statistically significant at the dose of 2 micrograms/kg. It is concluded that the castration-induced depression-like behavior in mice seems not to be due to the decreased levels and release of GnRH, and that GnRH has no antidepressant-like effect in mice, at least at our dose levels; however, GnRH seems to increase the number of cortical [3H]imipramine binding sites.


Assuntos
Comportamento Animal/efeitos dos fármacos , Proteínas de Transporte , Castração , Depressão/psicologia , Hormônio Liberador de Gonadotropina/farmacologia , Receptores de Droga , Animais , Córtex Cerebral/metabolismo , Feminino , Hormônio Liberador de Gonadotropina/metabolismo , Imipramina/metabolismo , Masculino , Camundongos , Orquiectomia , Ovariectomia , Receptores de Neurotransmissores/metabolismo
9.
Neurosci Lett ; 143(1-2): 181-4, 1992 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-1279474

RESUMO

A volume-controlled hemorrhagic shock was produced in anesthetized rats by intermittent bleeding from an iliac vein over a period of 20-30 min, until the carotid mean arterial pressure (MAP) stabilized around 20-24 mmHg. In this condition, which caused the death of all saline-treated animals within 25-30 min, the intravenous (i.v.) bolus injection of the adrenocorticotropin fragment 1-24 (ACTH(1-24)) at a dose of 160 micrograms/kg promptly restored MAP, as well as pulse pressure, heart rate and respiratory function, and greatly prolonged the survival time. Capsaicin (125 mg/kg cumulatively, s.c., 1 week before) completely prevented the anti-shock effect of ACTH(1-24), which, on the other hand, was shared by i.v. [Nle11]-substance P (SP) (200-300 micrograms/kg). Finally the SP-antagonist [D-Arg1,D-Pro2,D-Trp7,9,Leu11]-SP prevented the effect of ACTH(1-24). These results suggest that SP-containing nerve fibers are required for the effect of ACTH in hemorrhagic shock.


Assuntos
Hormônio Adrenocorticotrópico/antagonistas & inibidores , Capsaicina/farmacologia , Cosintropina/antagonistas & inibidores , Hemodinâmica/efeitos dos fármacos , Neurônios Aferentes/fisiologia , Proteínas Recombinantes , Choque Hemorrágico/fisiopatologia , Substância P/análogos & derivados , Substância P/fisiologia , Hormônio Adrenocorticotrópico/uso terapêutico , Vias Aferentes/efeitos dos fármacos , Animais , Capsaicina/toxicidade , Cosintropina/uso terapêutico , Endorfinas/fisiologia , Feminino , Masculino , Neurônios Aferentes/efeitos dos fármacos , Ratos , Ratos Wistar , Choque Hemorrágico/tratamento farmacológico , Substância P/antagonistas & inibidores , Substância P/farmacologia , Substância P/uso terapêutico , Taxa de Sobrevida
10.
Naunyn Schmiedebergs Arch Pharmacol ; 343(4): 427-30, 1991 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1852224

RESUMO

Cholinergic mechanisms are currently thought to play an essential role in blood pressure homeostasis. Here we show that, in urethane-anaesthetized rats bled to severe hemorrhagic shock, the i.v. administration of nicotine 0.2-50 micrograms/kg causes a prompt, sustained and dose-dependent improvement in cardiovascular and respiratory functions, the animals' survival rate being significantly higher than that of animals treated with saline. These effects are prevented by bilateral cervical vagotomy and by concurrent local anaesthesia of the carotid bodies, which suggests that stimulation of visceral afferents is the main mechanism of action of nicotine in hemorrhagic shock.


Assuntos
Nicotina/uso terapêutico , Choque/tratamento farmacológico , Animais , Pressão Sanguínea/efeitos dos fármacos , Feminino , Injeções Intravenosas , Masculino , Ratos , Ratos Endogâmicos , Ressuscitação , Vagotomia
11.
Naunyn Schmiedebergs Arch Pharmacol ; 342(1): 36-9, 1990 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2169595

RESUMO

In an experimental model of bleeding-induced hemorrhagic shock causing the death of all saline-treated rats within 30 min, the intravenous injection of ACTH-(1-24) at the dose of 160 micrograms/kg induced a sustained reversal of the shock condition, with almost complete recovery of blood pressure, pulse amplitude, respiratory rate, heart rate, and 100% survival, at least for the 2 h of observation. This effect of ACTH-(1-24) was prevented by the intracerebroventricular injection of 4-DAMP (a highly selective antagonist for M1 and M3 muscarinic receptors), but unaffected by the intracerebroventricular injection of pirenzepine (a highly selective antagonist for M1 muscarinic receptors). These data indicate that an essential step in the complex mechanism of the ACTH-induced shock reversal may be the activation of brain M3 muscarinic receptors.


Assuntos
Hormônio Adrenocorticotrópico/uso terapêutico , Química Encefálica/efeitos dos fármacos , Receptores Muscarínicos/fisiologia , Choque Hemorrágico/tratamento farmacológico , Hormônio Adrenocorticotrópico/antagonistas & inibidores , Animais , Pressão Sanguínea/efeitos dos fármacos , Feminino , Frequência Cardíaca/efeitos dos fármacos , Injeções Intraventriculares , Masculino , Piperidinas/farmacologia , Pirenzepina/farmacologia , Pulso Arterial/efeitos dos fármacos , Ratos , Ratos Endogâmicos , Choque Hemorrágico/fisiopatologia
12.
Life Sci ; 38(14): 1293-8, 1986 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-3485755

RESUMO

Intraperitoneal injection of putrescine induced dose-related hypothermia in rats. The effect was more pronounced at room temperature (22 degrees C) than in a warm environment (30 degrees C), the maximum hypothermia (-2.64 +/- 0.29 degrees C, 30 min. after treatment) being obtained with the dose of 300 mg/Kg and remaining significant throughout 3 hr of observation. Putrescine also had antipyretic activity, as it significantly reduced pyrogen-induced fever at a dose level (100 mg/Kg i.p.) ineffective in causing hypothermia in normal rats. The hypothermic and antipyretic effects of putrescine were not associated with any obvious sign of toxicity.


Assuntos
Anti-Inflamatórios não Esteroides , Temperatura Corporal/efeitos dos fármacos , Putrescina/farmacologia , Animais , Relação Dose-Resposta a Droga , Feminino , Injeções Intraperitoneais , Ratos , Ratos Endogâmicos , Temperatura
13.
Life Sci ; 44(8): 525-31, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2494400

RESUMO

alpha-Difluoromethylornithine (DFMO) directly infused into a brain-lateral ventricle (12.5, 25 and 50 micrograms/rat) dose- and time-dependently inhibited brain ODC activity. While having no influence per se on pain threshold, DFMO significantly inhibited the analgesic activity of morphine (15 mg/kg i.p.), this effect being obtained when brain ODC activity was reduced by at least 80%. On the other hand, DFMO had no influence on number and affinity of brain opiate binding sites. Morphine per se neither modified whole brain ODC activity nor significantly affected the ODC inhibitory effect of DFMO. In more discrete brain areas (midbrain, brainstem) morphine actually increased ODC activity. The present results indicate that brain ODC/polyamines system may play a role in the analgesic activity of opioids, probably at a post-receptorial level or through a non-opiate receptor-linked mechanism.


Assuntos
Analgesia , Encéfalo/enzimologia , Morfina , Ornitina Descarboxilase/fisiologia , Poliaminas/fisiologia , Animais , Encéfalo/efeitos dos fármacos , Di-Hidromorfina/metabolismo , Eflornitina/farmacologia , Feminino , Morfina/farmacologia , Inibidores da Ornitina Descarboxilase , Medição da Dor , Ratos , Ratos Endogâmicos
14.
Life Sci ; 45(2): 107-16, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2747421

RESUMO

In an experimental model of bleeding-induced hypovolemic shock causing the death of all saline-treated rats within 26 +/- 4 min, the intravenous injection of bombesin (2.5, 5 or 10 micrograms/kg) dose-dependently restored blood pressure, pulse amplitude, heart rate and respiratory function, and improved survival rate as assessed at the end of the experiment (2 h). The effect on cardiovascular and respiratory functions was prompt (within 1-2 min) and sustained. The release of cholecystokinin seems to be the main mechanism of action, because the anti-shock effect of bombesin is largely prevented by the CCK-antagonist, L-364,718.


Assuntos
Bombesina/farmacologia , Hemorragia/complicações , Choque/fisiopatologia , Animais , Benzodiazepinonas/farmacologia , Pressão Sanguínea/efeitos dos fármacos , Bombesina/antagonistas & inibidores , Colecistocinina/antagonistas & inibidores , Devazepida , Feminino , Injeções Intravenosas , Masculino , Pulso Arterial/efeitos dos fármacos , Ratos , Ratos Endogâmicos , Respiração/efeitos dos fármacos , Choque/etiologia
15.
Life Sci ; 49(24): 1815-21, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1943485

RESUMO

In a rat model of volume-controlled hemorrhagic shock causing the death of all saline-treated animals within 30 min of treatment, the intravenous bolus injection of thyrotropin- releasing hormone tartrate (TRH-T) at the dose of 4 mg/kg induced the prompt and sustained disappearance of the ECG and EEG signs of heart and brain ischemia, along with the reversal of hypotension and respiratory depression and with 100% survival rate at the end of the 2 h observation period. These data confirm that, in a pre-terminal condition induced by massive hemorrhage, timely treatment with TRH-T will restore heart and brain perfusion to levels compatible with survival and with functional recovery from ischemia and maintain it at those levels for some hours.


Assuntos
Circulação Cerebrovascular/efeitos dos fármacos , Circulação Coronária/efeitos dos fármacos , Choque Hemorrágico/fisiopatologia , Hormônio Liberador de Tireotropina/farmacologia , Animais , Eletrocardiografia/efeitos dos fármacos , Eletroencefalografia/efeitos dos fármacos , Feminino , Masculino , Ratos , Ratos Endogâmicos
16.
Resuscitation ; 23(2): 113-20, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1321471

RESUMO

In anesthetized rats, step-wise bleeding to a severe condition of hemorrhagic shock causes a decrease in arterial and venous pH and in venous PO2 and SO2 and an increase in arterial PO2 and in venous PCO2 and lactic acid. The intravenous bolus injection of ACTH-(1-24) (160 micrograms/kg)--which causes a rapid and sustained reversal of the shock condition--produces a gradual and almost complete recovery (within 60 min) of venous PO2, PCO2 and SO2; on the other hand, the normalization of blood pH and lactate is preceded by a further worsening during the first minutes after treatment. On the whole, these data are compatible with the ACTH-(1-24)-induced mobilization of the residual blood--which is pooled in poorly oxygenated tissues--and with the improved circulatory and respiratory functions.


Assuntos
Acidose/etiologia , Cosintropina/farmacologia , Hemorragia/complicações , Hipóxia/etiologia , Animais , Artérias , Bicarbonatos/sangue , Dióxido de Carbono/sangue , Feminino , Hemorragia/sangue , Concentração de Íons de Hidrogênio , Masculino , Oxigênio/sangue , Pressão Parcial , Ratos , Ratos Endogâmicos , Choque Hemorrágico/sangue , Choque Hemorrágico/complicações , Veias
17.
Physiol Behav ; 37(5): 827-31, 1986.
Artigo em Inglês | MEDLINE | ID: mdl-3022319

RESUMO

Four times daily from postnatal day 1 to 15, rats were stressed either by being removed from the maternity cage (manipulation stress, MS) or by being placed on a hotplate at 55 degrees C (pain stress, PS). When 70 days old, they were examined for sensitivity to pain and to the analgesic effect of morphine, and for brain opiate receptors. Pain sensitivity of MS and PS rats was not significantly different from that of controls. The analgesic activity of morphine, assessed by the hotplate test at 49 degrees C, was significantly reduced in MS rats, while in PS rats it was similar to that in controls. 3H-dihydromorphine binding studies performed on whole brain synaptic membranes showed a reduction in the maximum number of binding sites in both MS and PS rats; on the other hand, the affinity constant was higher in PS rats, while in MS rats it was similar to that of controls. These data show that the repeated stress of removal from the mother during the first 15 days of life induce a reduction in the number of brain opiate receptors with reduced activity of morphine, while in rats exposed to repeated removal stress associated with painful stimuli the reduction in the number of brain opiate receptors seems to be counterbalanced by their higher affinity.


Assuntos
Morfina/farmacologia , Dor/fisiopatologia , Estresse Psicológico/fisiopatologia , Animais , Animais Recém-Nascidos , Química Encefálica , Privação Materna , Dor/prevenção & controle , Ratos , Receptores Opioides/análise , Membranas Sinápticas/análise
18.
Physiol Behav ; 45(5): 1067-8, 1989 May.
Artigo em Inglês | MEDLINE | ID: mdl-2780868

RESUMO

In the tail suspension test (an animal model of depression) the duration of immobility during the 6 min of observation was 56.84 +/- 6.54 sec in sham-ovariectomized mice and 113.11 +/- 7.86 sec 30-32 days after ovariectomy. Estradiol (10, 100 or 1,000 micrograms/kg) and progesterone (50, 1,000 or 10,000 micrograms/kg), subcutaneously injected daily 4 times before the test, restored the duration of immobility in ovariectomized mice to normal, while having no effect on sham-operated animals. On the other hand, desipramine (20 mg/kg IP 1 hr before testing) significantly reduced the duration of immobility both in ovariectomized and in sham-operated mice. These data indicate that ovarian sex hormones, while having no "antidepressant," desipramine-like, effect on the behavior of intact adult female mice, have such an effect in ovariectomized mice, and enable the animal to cope in a "normal" way with adverse environmental situations.


Assuntos
Comportamento Animal/efeitos dos fármacos , Depressão/tratamento farmacológico , Estradiol/farmacologia , Ovariectomia , Progesterona/farmacologia , Animais , Desipramina/farmacologia , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Feminino , Camundongos
19.
J Pharm Pharmacol ; 41(9): 651-3, 1989 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-2573715

RESUMO

Putrescine, (150-300 mg kg-1 i.v.) injected into anaesthetized rats reversed aconitine-induced arrhythmia and restored sinus rhythm. In the same experimental model, quinidine and lignocaine had a transient therapeutic effect, procainamide was practically ineffective and verapamil worsened the aconitine arrhythmia, causing the death of all treated animals. These data demonstrate that putrescine has an antiarrhythmic effect in an experimental model particularly resistant to usual antiarrhythmic treatments.


Assuntos
Aconitina/antagonistas & inibidores , Aconitum/análogos & derivados , Antiarrítmicos , Arritmias Cardíacas/induzido quimicamente , Putrescina/farmacologia , Animais , Arritmias Cardíacas/fisiopatologia , Eletrocardiografia , Feminino , Injeções Intravenosas , Ratos , Ratos Endogâmicos
20.
Braz J Med Biol Res ; 35(11): 1333-7, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12426633

RESUMO

The 32-bp deletion in the HIV-1 co-receptor CCR5 confers a high degree of resistance to HIV-1 infection in homozygous individuals for the deleted allele and partial protection against HIV-1 during disease progression in heterozygotes. Natural ligands for CCR5, MIP-1alpha, MIP-1beta and RANTES, have been shown to inhibit HIV replication in CD4+ T cells. In the present study, we examined the CCR5 genotype by PCR and the plasma levels of RANTES and MIP-1alpha by ELISA among blood donors (N = 26) and among HIV-1-infected individuals (N = 129). The control group consisted of healthy adult volunteers and HIV-1-infected subjects were an asymptomatic and heterogeneous group of individuals with regard to immunologic and virologic markers of HIV-1 disease. The frequency of the CCR5 mutant allele (Delta32ccr5) in this population was 0.032; however, no Delta32ccr5 homozygote was detected. These results could be related to the intense ethnic admixture of the Brazilian population. There was no correlation between circulating beta-chemokines (MIP-1alpha, RANTES) and viral load in HIV-infected individuals. RANTES concentrations in plasma samples from HIV+ patients carrying the homozygous CCR5 allele (CCR5/CCR5) (28.23 ng/ml) were higher than in the control samples (16.07 ng/ml; P<0.05); however, this HIV+ patient group (mean 26.23 pg/ml) had significantly lower concentrations of MIP-1alpha than those observed in control samples (mean 31.20 pg/ml; P<0.05). Both HIV-1-infected and uninfected individuals heterozygous for the Delta32ccr5 allele had significantly lower concentrations of circulating RANTES (mean 16.07 and 6.11 ng/ml, respectively) than CCR5/CCR5 individuals (mean 28.23 and 16.07 ng/ml, respectively; P<0.05). These findings suggest that the CCR5 allele and beta-chemokine production may affect the immunopathogenesis of HIV-1.


Assuntos
Quimiocina CCL5/sangue , Infecções por HIV/sangue , HIV-1/genética , Proteínas Inflamatórias de Macrófagos/sangue , Receptores CCR5/genética , Adulto , Alelos , Doadores de Sangue , Estudos de Casos e Controles , Quimiocina CCL3 , Quimiocina CCL4 , Quimiocina CCL5/biossíntese , Ensaio de Imunoadsorção Enzimática , Genótipo , Infecções por HIV/genética , Infecções por HIV/imunologia , Humanos , Proteínas Inflamatórias de Macrófagos/biossíntese , Reação em Cadeia da Polimerase , Carga Viral
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