Effects of atropine on respiratory sinus arrhythmia (RSA) in the rhesus macaque.
Twelve juvenile to adult rhesus macaques were administered atropine sulfate (0, 14, 44, and 140 mcg/kg IM). The amplitude of the respiratory sinus arrhythmia (RSA) in the rhesus macaque was estimated using a Vagal Tone Monitor (VTM). The estimate of RSA (termed V; vagal tone) was significantly reduced for nearly 3 hr after all doses of atropine, suggesting possible central nervous system effects. Heart period (R-R interval) was reduced briefly after dosing. Overall heart period variability (HPV) was depressed after all doses of atropine. The amount of atropine required to decrease HPV and V by 30% was similar to that reported for the human. The rhesus monkey was determined to have little resting vagal tone as estimated by V. A large slow wave oscillation contributed to the overall variability in heart period. It is concluded that the rhesus monkey exhibits a similar sensitivity to atropine as did the human and, therefore, provides a useful model for the study of cholinergic drug actions and their effects on RSA.
Jansen
H T
HT
Department of Veterinary Biosciences, University of Illinois, Urbana 61801.
Dellinger
J A
JA
D000818:Animals; D001146:Arrhythmia, Sinus / Q000188:drug therapy* / Q000503:physiopathology; D001285:Atropine / Q000494:pharmacology*; D004562:Electrocardiography; D008253:Macaca mulatta; D012119:Respiration; D014630:Vagus Nerve / Q000503:physiopathology
D001285:Atropine