Vol. 277, Issue 4, R1057-R1062, October 1999
Role of cholinergic receptors in adrenal catecholamine
secretion in spontaneously hypertensive rats
Takahiro
Nagayama1,
Takayuki
Matsumoto1,
Makoto
Yoshida1,
Mizue
Suzuki-Kusaba1,
Hiroaki
Hisa1,
Tomohiko
Kimura2, and
Susumu
Satoh1
1 Laboratory of Pharamacology,
Graduate School of Pharmaceutical Sciences, Tohoku University,
Sendai 980-8578; and 2 Department
of Dental Pharmacology, The Nippon Dental University School of
Dentistry at Niigata, Niigata 951-8580, Japan
We
investigated the role of nicotinic and muscarinic receptors in
secretion of catecholamines induced by transmural electrical stimulation (ES) from isolated perfused adrenal glands of spontaneously hypertensive rats (SHRs) and normotensive Wistar-Kyoto (WKY) rats. ES
(1-10 Hz) produced frequency-dependent increases in epinephrine (Epi) and norepinephrine (NE) output as measured in
perfusate. The ES-induced increases in NE output, but not Epi output,
were significantly greater in adrenal glands of SHRs than in those of
WKY rats. Hexamethonium (10-100 µM) markedly
inhibited the ES-induced increases in Epi and NE output from adrenal
glands of SHRs and WKY rats. Atropine (0.3-3 µM) inhibited the
ES-induced increases in Epi and NE output from adrenal glands of SHRs,
but not from those of WKY rats. These results suggest that endogenous acetylcholine-induced secretion of adrenal catecholamines is
predominantly mediated by nicotinic receptors in SHRs and WKY rats and
that the contribution of muscarinic receptors may be different between these two strains.
adrenal gland; nicotinic receptors; muscarinic receptors; hexamethonium; atropine
