You should seek the advice of your veterinarian if your pet is ill as only he or she can correctly advise on the diagnosis and recommend the treatment that is most appropriate for your pet.

Abstract
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 inderal 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.

Reference

FIZIOLOGICHESKII ZHURNAL SSSR IMENI IM SECHENOVA = THE JOURNAL OF ,   63(8):1134-1143 1977     

Updated January 2016