RESUMO
The simulation of the hypo- and hyperactivity of the hypophysis-adrenocortical system induced considerable changes in the reactivity of alpha 2-adrenoceptors, as well as in the resistance of the organism to stressful influences. The findings support the assumption that the blockade of alpha 2-adrenoceptors is one of the key features in the adaptive mechanism of the glycocorticoid hormones action.
Assuntos
Antagonistas Adrenérgicos alfa/farmacologia , Sistema Hipófise-Suprarrenal/fisiologia , Receptores Adrenérgicos alfa/fisiologia , Estresse Psicológico/fisiopatologia , Doença Aguda , Adrenalectomia , Agonistas alfa-Adrenérgicos/farmacologia , Animais , Estado de Descerebração/fisiopatologia , Hemorragia/fisiopatologia , Hipofisectomia , Hipóxia/fisiopatologia , Ataque Isquêmico Transitório/fisiopatologia , Sistema Hipófise-Suprarrenal/efeitos dos fármacos , Ratos , Receptores Adrenérgicos alfa/efeitos dos fármacos , Restrição Física , Simpatectomia QuímicaRESUMO
Experiments were conducted on pithed rats with acute pancreatitis and on falsely operated on animals (ether-laparotomy stress) to study the reactivity of vascular alpha 1- and alpha 2-adrenoreceptors and its role in changes in arterial pressure. Selective change in the reactivity of alpha 2-adrenoceptors alone was revealed in both groups. Stable reduction of vascular alpha 2-adrenergic reactivity (by 57-58%) and arterial pressure was recorded in animals with acute pancreatitis. In falsely operated on animals, in contrast, the values of these indices exceeded the control level. In animals with a functioning central nervous system inhibition of alpha 2-adrenergic reactivity correlated with change in arterial pressure only in the initial (3-4 hours) hemorrhagic phase of acute pancreatitis.
Assuntos
Pressão Sanguínea/fisiologia , Pancreatite/fisiopatologia , Receptores Adrenérgicos alfa/fisiologia , Doença Aguda , Agonistas alfa-Adrenérgicos/farmacologia , Animais , Azepinas/farmacologia , Pressão Sanguínea/efeitos dos fármacos , Clonidina/farmacologia , Estado de Descerebração/fisiopatologia , Laparotomia , Masculino , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/fisiopatologia , Fenilefrina/farmacologia , Ratos , Receptores Adrenérgicos alfa/efeitos dos fármacosRESUMO
The effect of adrenomimetics on the central alpha 2-adrenoreceptors responsible for mydriasis was studied. It was found that alpha 2-adrenomimetic azepoxole (BHT-933) exerts no effect on the central alpha 2-adrenoreceptors providing mydriasis.
