Neurochemical regulation of cough response to capsaicin in guinea-pigs.
Neurochemical regulation of cough response to capsaicin in guinea-pigs.
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DOI:
10.1046/j.1474-8673.2002.00242.x
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发表时间:
2002-02-01
期刊:
影响因子:
--
通讯作者:
Sasaki, H.
中科院分区:
文献类型:
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作者:
Li, J. Q.;Jia, Y. X.;Sasaki, H.
Although monumental efforts have been made to define the action sites of cough, the importance of neurotransmitter systems in the cough reflex has received limited attention. We studied the roles for four major neurotransmitters (acetylcholine, histamine, serotonin (5-hydroxytryptamine, 5-HT) and dopamine) in the modulation of the cough reflex. Atropine (muscarinic cholinergic blocking agent), pyrilamine maleate (PM, histamine H1 blocker), cimetidine (histamine H2 blocker), 8-hydroxy-2-(di-n-propylamino)-tetralin (8-OH-DPAT, specific 5-HT1A receptor agonist) and SCH-23390 (selective dopamine D1 receptor antagonist) were examined on the cough response to inhaled capsaicin in conscious guinea-pigs. All the drugs significantly decreased the number of capsaicin-induced coughs in a dose-dependent manner. To compare the sensitivity of these drugs on cough response, we calculated the effective doses for 50% inhibition of cough (ED50) when the animals were exposed to 3 X 10-4 M capsaicin. The ED50 values were 0.03 muM kg-1 for atropine, 0.2 muM kg-1 for 8-OH-DPAT, 6.2 muM kg-1 for SCH-23390, 8.5 muM kg-1 for PM and 13.9 muM kg-1 for cimetidine. These findings indicated that all these four neurotransmitters may be involved in the regulation of the cough reflex. Multiple changes of these neurotransmitters in disorders of the central nervous system might synergically affect the cough reflex.