The sympathetic nervous system does not participate in the development of atropine tachycardia
Smirnov, V.M.
Biulleten' Eksperimental'noi Biologii i Meditsiny 118(9): 234-237
1994
ISSN/ISBN: 0365-9615 PMID: 7819547 Document Number: 432725
According to current concepts, vagus produces a constant (tonic) inhibitory effect on the cardiac function in different animal species. However, some recent experimental studies indicate no expressed vagal tone. Excitation of the sympathetic-adrenal system is therefore believed to cause atropine-dependent tachycardia. As observed in chronic and acute experiments in rats, pigeons and dogs, blockade of the sympathetic nervous system did not eliminate atropine- and methacin-dependent tachycardia. In normal conditions, the cardiac function is controlled by the vagus and humoral agents circulating in the blood.