[Role of the hypothalamus and pituitary gland in the development of pancreatic islet sensitivity to glucose in fetal rats].
Differences in the pattern of the development of three enzymes of the plasma membrane have been established. The activity of Na, K-ATPase progressively increases, that of adenylate cyclase decreases, whereas the activity of 5-nucleotidase undergoes only slight changes during embryogenesis. Differences between these enzymes were also found with respect to the development of their sensitivity to the regulatory effects of catecholamines. Adrenaline reactivity of adenylate cyclase may be detected already in embryogenesis; it is lower than that in definite muscle tissue increasing during further ontogenesis. Catecholamine reactivity was not found in Na, K-ATPase and 5-nucleotidase up to the 17th day of incubation of chick embryos. The effect of adrenalin was observed at later stages of ontogenesis, it may be initiated by exogeneous cAMP and protein kinase. At postembryonic stages, similarity in the behavior of these enzymes was found with respect to the presence and pattern of their reaction to adrenalin (stimulation), as well as with respect to temporal dynamics of the effect. The data obtained indicate the existence of close connections between these enzymes, which are realized in the sequence adrenoreceptor-adenylate cyclase-cAMP-protein kinase-effector proteins.
D000324:Adrenocorticotropic Hormone / Q000494:pharmacology; D000818:Animals; D005260:Female; D005947:Glucose / Q000494:pharmacology*; D013006:Growth Hormone / Q000494:pharmacology; D007016:Hypophysectomy; D007030:Hypothalamo-Hypophyseal System / Q000196:embryology*; D007328:Insulin / Q000378:metabolism*; D000078790:Insulin Secretion; D007515:Islets of Langerhans / Q000196:embryology* / Q000378:metabolism; D051381:Rats
D007328:Insulin; D000324:Adrenocorticotropic Hormone; D013006:Growth Hormone; D005947:Glucose
Znachenie gipotalamusa i gipofiza v razvitii chuvstvitel'nosti pankreaticheskikh ostrovkov ploda krysy k deĭstviiu gliukozy.