Cardiac responses induced by nicotinic activation of canine right atrial ganglionated plexus / 中国药理学通报

ABSTRACT

It was found that there were 31?s 13 ganglia or 1983 ?s 331 neurons ( n = 6) in canine right atrial ganglionated plexus (RAGP). Nicotine (100 ?g) was administered to the plexus in 30 anesthetized open-chest dogs. Either positive or negative inotropic and chronotropic responses were elicited. Control injections of 0. 1 m1 NS into RAGP and injections of nicotine (100 ?g and 200?g) did not elicite any cardiac responses. Following acute decentralzation of hearts, nicotine (100 ?g ) was againadministered to RAGP. Some positive and negative responses were still elicited, but frequency of the responses was reduced. It is concluded that nicotine can directly activate efferent sympathetic and parasympathetic neurons of RAGP. and indirectly activate them by stimulation of afferent neurons, these nicotine sensitive cardiac neurons can modulate cardiac function in ifferent tendencies.