RESUMO
In the hormone-dependent prostate inflammation model induced by implantation of slow-releasing pellets (50 mg testosterone and 5 mg estradiol) to Noble male rats, intragastric administration of Afala at a dose of 7.5 ml/kg for 18 weeks reduced the number of inflamed prostatic acini. The effect of afala was comparable with that of antiestrogen ICI 182,780 (3 mg/kg subcutaneously twice a week for 18 weeks). Prolonged treatment with hormones in high doses induced severe inflammation of the prostate tissue, which was not terminated by the test preparations. As differentiated from the antiestrogen ICI 182,780, afala did not induce body weight gain and decrease in pituitary weight in experimental animals in comparison with the control group.
Assuntos
Anticorpos/farmacologia , Estradiol/análogos & derivados , Inflamação/tratamento farmacológico , Próstata/efeitos dos fármacos , Análise de Variância , Animais , Estradiol/efeitos adversos , Estradiol/farmacologia , Fulvestranto , Técnicas Histológicas , Inflamação/induzido quimicamente , Inflamação/patologia , Masculino , Tamanho do Órgão/efeitos dos fármacos , Próstata/patologia , Ratos , Testosterona/efeitos adversos , Aumento de Peso/efeitos dos fármacosRESUMO
The commonly used sedative α2-adrenoceptor agonist dexmedetomidine has adverse cardiovascular effects in dogs that can be prevented by concomitant administration of the peripherally acting α2-adrenoceptor antagonist MK-467. An ancillary effect of dexmedetomidine is to decrease insulin release from the pancreas, whereas MK-467 stimulates insulin release. This study assessed the effects of co-administered dexmedetomidine and MK-467 in a canine glibenclamide-induced hypoglycaemia model. In a randomised, cross-over experiment, eight beagle dogs received five intravenous treatments, comprising two administrations of saline, with dexmedetomidine or dexmedetomidine and MK-467, and three administrations of glibenclamide, with saline, dexmedetomidine or dexmedetomidine and MK-467. Plasma concentrations of glucose, lactate, insulin, glucagon and the test drugs were monitored. Administration of glibenclamide significantly increased insulin secretion and decreased blood glucose concentrations. Dexmedetomidine counteracted glibenclamide-evoked hypoglycaemia. This was opposed by the α2-adrenoceptor antagonist MK-467, but the glibenclamide-evoked hypoglycaemia was not potentiated by co-administration of dexmedetomidine and MK-467. None of the dogs developed uncontrolled hypoglycaemia. Thus, the combination of dexmedetomidine and MK-467 appeared to be safe in this canine hypoglycaemia model. Nevertheless, when MK-467 is used to alleviate the undesired cardiovascular effects of α2-adrenoceptor agonists in dogs, it should be used with caution in animals at risk for hypoglycaemia because of its insulin-releasing and hypoglycaemic effects.
Assuntos
Agonistas de Receptores Adrenérgicos alfa 2/farmacologia , Dexmedetomidina/farmacologia , Hipnóticos e Sedativos/farmacologia , Hipoglicemia/tratamento farmacológico , Quinolizinas/farmacologia , Agonistas de Receptores Adrenérgicos alfa 2/administração & dosagem , Anestesia Intravenosa/veterinária , Animais , Glicemia/efeitos dos fármacos , Estudos Cross-Over , Dexmedetomidina/administração & dosagem , Modelos Animais de Doenças , Cães , Relação Dose-Resposta a Droga , Quimioterapia Combinada , Feminino , Glucagon/sangue , Glucagon/efeitos dos fármacos , Glibureto , Hipnóticos e Sedativos/administração & dosagem , Hipoglicemia/induzido quimicamente , Hipoglicemiantes , Insulina/sangue , Insulina/metabolismo , Masculino , Quinolizinas/administração & dosagem , Distribuição Aleatória , Resultado do TratamentoRESUMO
Obesity and white adipose tissue (WAT) inflammation are associated with enhanced aromatization in women, but little is known about the regulation of aromatase (CYP19A1) gene expression in male WAT. We investigated the impact of weight gain and WAT inflammation on the regulation of CYP19A1 in males, by utilizing the hARO-Luc aromatase reporter mouse model containing a >100-kb 5'-region of the human CYP19A1 gene. We show that hARO-Luc reporter activity is enhanced in WAT of mice with increased adiposity and inflammation. Dexamethasone and TNFα, as well as forskolin and phorbol 12-myristate 13-acetate, upregulate hARO-Luc activity, suggesting the involvement of promoters I.4 and I.3/II. Furthermore, we show that diet enriched with antioxidative plant polyphenols attenuates WAT inflammation and hARO-Luc activity in obese males. In conclusion, our data suggest that obesity-associated WAT inflammation leads to increased peripheral CYP19A1 expression in males, and that polyphenol-enriched diet may have the potential to attenuate excessive aromatization in WAT of obese men.