[Age-related characteristics of adrenergic regulation of the contractile function of the heart in hypoxia].
Experiments were performed on isolated hearts of adult (8-10 months old) and aged (24-26 months old) rats perfused with the Krebs-Henseleit solution according to the method of Langendorf. It was demonstrated that when oxygen supply was insufficient (pO2 of the perfusion solution-100 mm Hg), the chronotropic reaction of the heart to the stimulation of alpha- and beta-adrenergic receptors with phenylephrine hydrochloride (5 x 10(-7)--10(-5) M) and isoprenaline (10(-9)--10(-6) M), respectively, increased in adult rats and decreased in aged animals. Positive inotropic effects of adrenoagonists in hypoxic hearts diminished but their values as well as those at adequate oxygenation (pO2 = 600 mm Hg) were higher in aged rats. Stimulation of adrenoreceptors in the case of inadequate oxygenation increased hypoxic myocardial contracture, the increase being greater in adult rats.
Lobanok
L M
LM
Kirienkov
A E
AE
D000367:Age Factors; D000818:Animals; D000860:Hypoxia / Q000503:physiopathology*; D066298:In Vitro Techniques; D007545:Isoproterenol / Q000494:pharmacology*; D008297:Male; D009200:Myocardial Contraction / Q000187:drug effects*; D010656:Phenylephrine / Q000494:pharmacology*; D051381:Rats; D011942:Receptors, Adrenergic, alpha / Q000187:drug effects*; D013268:Stimulation, Chemical
D011942:Receptors, Adrenergic, alpha; D010656:Phenylephrine; D007545:Isoproterenol
Vozrastnye osobennosti adrenergicheskoĭ reguliatsii sokratitel'noĭ funktsii serdtsa v usloviiakh gipoksii.