[Calcium and the permissive effect of glucocorticoids: the role of glucocorticoids in an adrenaline-induced increase in the rate of calcium absorption by the ventricular tissue of the rat heart].
It was demonstrated in rat experiments that the ability of the myocardial ventricles to increase 45Ca absorption after the injection of adrenaline was disturbed on the 3rd--5th day following adrenalectomy. The decrease in sensitivity to adrenaline occurred in two phases and was delayed essentially after a fall in the concentration of glucocorticoids in circulation. Chronic in vivo injection of hydrocortisone (2.5 mg per rat) into these animals for 3--5 days restored the effect of catecholamine to a great extent. The restorative effect was weaker when the rats were given a single intravenous hydrocortisone infusion 6 hours before being killed. Increase of the single intravenous dose of the hormone to 5 and 7.5 mg per rat reduced its effect. The authors assume that the described permissive effect of glucocorticoids is determined not by their direct interaction with the cytoplasmic membrane but by hormone induced intracellular synthesis of proteins capable of participating in the regulation of permeability to ions.
D000042:Absorption; D000315:Adrenalectomy; D000818:Animals; D002118:Calcium / Q000378:metabolism*; D004837:Epinephrine / Q000494:pharmacology*; D005938:Glucocorticoids / Q000502:physiology*; D006321:Heart / Q000187:drug effects*; D006352:Heart Ventricles / Q000378:metabolism; D006854:Hydrocortisone / Q000494:pharmacology; D008297:Male; D009206:Myocardium / Q000378:metabolism*; D051381:Rats; D013997:Time Factors
D005938:Glucocorticoids; D002118:Calcium; D006854:Hydrocortisone; D004837:Epinephrine
Kal'tsiĭ i permissivnyĭ éffekt gliukokortikoidov: o roli gliukokortikoidov v indutsiruemom adrenalinom uvelichenii skorosti pogloshcheniia kal'tsiia tkan'iu zheludochkov serdtsa krys.