[Reduction of isoprenaline induced tachycardia in pregnant rats. Role of a serum factor].
The in vivo isoprenaline (50 microgram/kg) induced tachycardia (beta 1 adrenergic stimulant effect) was decreased in pregnant (20th day) Rats compared to non pregnant Rats. The in vitro positive chronotropic effect of isoprenaline (10 ng/ml) on cultured Rat heart cells was abolished by pregnant Rat serum whereas progesterone (0.10 to 5 microgram/ml) or oestradiol (0.1 to 25 microgram/ml) were ineffective. The decreased beta 1 adrenergic responsiveness in pregnant Rats could be related to a seric factor, different from these two hormones.
D000818:Animals; D001790:Blood Physiological Phenomena; D003470:Culture Media; D004958:Estradiol / Q000494:pharmacology; D005260:Female; D006339:Heart Rate / Q000187:drug effects*; D006801:Humans; D066298:In Vitro Techniques; D007545:Isoproterenol / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D009206:Myocardium / Q000166:cytology; D011247:Pregnancy; D011270:Pregnancy, Animal / Q000187:drug effects*; D011374:Progesterone / Q000494:pharmacology; D051381:Rats
D003470:Culture Media; D011374:Progesterone; D004958:Estradiol; D007545:Isoproterenol
Diminution de l'effet tachycardisant de l'isoprénaline chez les rattes gravides. Rôle d'un facteur sérique.