Frol'kis V V, Verkhratskiĭ N S, Shevchuk V G
Fiziol Zh SSSR Im I M Sechenova. 1977 Aug;63(8):1134-43.
The hemodynamic changes and myocardium contractile capacity following the extracardiac nerves stimulation with acetylcholine, norepinephrine, inderal, regitin and atropine, as well as the activity of main enzymes of cholinergic and adrenergic metabolism, were studied in albino rats, rabbits, and cats of various age. With ageing, the thresholds of vagal and sympathetic nerves influences on the heart increased, the sensitivity of heart to acetylcholine and norepinephrine changed. In old animals, smaller atropine and in deral doses blocked the respective cholinergic and beta-adrenergic reactions. Alterations of transmitters metabolism play an important role in the mechanism of age-induced changes in nervous control of cardiac function.
