ALPHA-ADRENOCEPTOR MODULATION OF THE EFFERENT FUNCTION OF CAPSAICIN-SENSITIVE SENSORY NEURONS IN GUINEA-PIG ISOLATED ATRIA

被引:13
作者
AMERINI, S
RUBINO, A
MANTELLI, L
LEDDA, F
机构
[1] Department of Pharmacology, University of Florence, Florence, 50134
关键词
NORADRENALINE; ALPHA-ADRENOCEPTORS; CAPSAICIN; SENSORY NEURONS; GUINEA-PIG HEART;
D O I
10.1111/j.1476-5381.1992.tb09083.x
中图分类号
R9 [药学];
学科分类号
1007 ;
摘要
1 Transmural nerve stimulation of guinea-pig atria, obtained from animals pretreated with reserpine (5 mg kg-1, i.p.), in the presence of atropine 1-mu-M and of the beta-adrenoceptor blocker CGP 20712A 1-mu-M, induced a positive inotropic effect which was reduced by the calcitonin gene-related peptide (CGRP) antagonist hCGRP-(8-37) and abolished by pretreatment with capsaicin 1-mu-M. 2 Noradrenaline concentration-dependently (0.01 - 10-mu-M) reduced the increase in cardiac contractility induced by transmural nerve stimulation. The inhibitory effect of noradrenaline was antagonized by yohimbine (0.5 - 1-mu-M), in a dose-dependent manner. Prazosin (0.5 - 1-mu-M) antagonized the effect of noradrenaline and this effect was independent of concentration. 3 In the presence of yohimbine, the lower part of the inhibitory-response curve for noradrenaline was slightly but significantly shifted by prazosin. A similar degree of antagonism was observed in the presence of 1-mu-M phenoxybenzamine. 4 The selective alpha(2) agonists BHT 920 and clonidine reduced, in the same concentration-range (0.01 - 1-mu-M), the cardiac response to transmural nerve stimulation in a yohimbine-sensitive fashion. 5 Phenylephrine (0.1 - 100-mu-M) and methoxamine (1 - 300-mu-M) also induced an inhibitory effect on transmural nerve stimulation. The effect of phenylephrine was antagonized by yohimbine (1-mu-M) more efficiently than by prazosin (0.5-mu-M). 6 These results are in keeping with the presence of inhibitory prejunctional alpha(2)-adrenoceptors on cardiac sensory nerve endings which modulate the efferent function of capsaicin-sensitive neurones.
引用
收藏
页码:947 / 953
页数:7
相关论文
共 46 条
[11]   PREJUNCTIONAL MODULATORY ACTION OF NEUROPEPTIDE-Y ON PERIPHERAL TERMINALS OF CAPSAICIN-SENSITIVE SENSORY NERVES [J].
GIULIANI, S ;
MAGGI, CA ;
MELI, A .
BRITISH JOURNAL OF PHARMACOLOGY, 1989, 98 (02) :407-412
[12]  
GRUNDSTROM N, 1984, ACTA PHARMACOL TOX, V54, P8
[13]   INVIVO DEMONSTRATION OF ALPHA-2-ADRENOCEPTOR-MEDIATED INHIBITION OF THE EXCITATORY NON-CHOLINERGIC NEUROTRANSMISSION IN GUINEA-PIG AIRWAYS [J].
GRUNDSTROM, N ;
ANDERSSON, RGG .
NAUNYN-SCHMIEDEBERGS ARCHIVES OF PHARMACOLOGY, 1985, 328 (03) :236-240
[14]   MOLECULAR CHARACTERIZATION OF ALPHA-1-ADRENOCEPTORS AND ALPHA-2-ADRENOCEPTORS [J].
HARRISON, JK ;
PEARSON, WR ;
LYNCH, KR .
TRENDS IN PHARMACOLOGICAL SCIENCES, 1991, 12 (02) :62-67
[15]  
HIRST GDS, 1980, NATURE, V288, P301
[16]   EFFECTS OF CALCITONIN GENE-RELATED PEPTIDE (CGRP) AND ISOPROTERENOL ON THE CONTRACTILITY AND ADENYLATE-CYCLASE ACTIVITY IN THE RAT-HEART [J].
ISHIKAWA, T ;
OKAMURA, N ;
SAITO, A ;
GOTO, K .
JOURNAL OF MOLECULAR AND CELLULAR CARDIOLOGY, 1987, 19 (08) :723-727
[17]   IS THERE A 3RD HEART BETA-ADRENOCEPTOR [J].
KAUMANN, AJ .
TRENDS IN PHARMACOLOGICAL SCIENCES, 1989, 10 (08) :316-320
[18]   INVESTIGATION INTO DIFFERENT TYPES OF POSTSYNAPTIC AND PRESYNAPTIC ALPHA-ADRENOCEPTORS AT CARDIOVASCULAR SITES IN RATS [J].
KOBINGER, W ;
PICHLER, L .
EUROPEAN JOURNAL OF PHARMACOLOGY, 1980, 65 (04) :393-402
[19]   DIFFERENCES BETWEEN THE PREJUNCTIONAL EFFECTS OF PHENYLEPHRINE AND CLONIDINE IN GUINEA-PIG ISOLATED ATRIA [J].
LEDDA, F ;
MANTELLI, L .
BRITISH JOURNAL OF PHARMACOLOGY, 1984, 81 (03) :491-497
[20]   NEUROPEPTIDE-Y (NPY)-LIKE IMMUNOREACTIVITY IN PERIPHERAL NORADRENERGIC NEURONS AND EFFECTS OF NPY ON SYMPATHETIC FUNCTION [J].
LUNDBERG, JM ;
TERENIUS, L ;
HOKFELT, T ;
MARTLING, CR ;
TATEMOTO, K ;
MUTT, V ;
POLAK, J ;
BLOOM, S ;
GOLDSTEIN, M .
ACTA PHYSIOLOGICA SCANDINAVICA, 1982, 116 (04) :477-480