Effects of N-methyl-D-aspartate antagonists on the cough reflex.
The effects of antagonists of N-methyl-D-aspartate (NMDA) on the capsaicin-induced cough reflex in rats were studied. Intracisternal (i. cist.) injection of MK-801, a non-competitive antagonist of NMDA, significantly decreased the number of coughs in a dose-dependent manner. The competitive antagonists of NMDA, 2-DL-amino-5-phosphonovalerate and 2-DL-amino-7-phosphonoheptanoate, also decreased the number of coughs after i. cist. injection. The antitussive potencies of both the competitive and non-competitive antagonists were similar to that of dextromethorphan. Intraperitoneal injection of MK-801 also decreased the number of coughs in a dose-dependent manner. These data suggest that excitatory amino acid neurotransmitters and NMDA receptors may be involved in the regulation of the cough reflex.
Kamei
J
J
Department of Pharmacology, School of Pharmacy, Hoshi University, Tokyo, Japan.
Tanihara
H
H
Igarashi
H
H
Kasuya
Y
Y
D000818:Animals; D000927:Anticonvulsants / Q000494:pharmacology; D001224:Aspartic Acid / Q000031:analogs & derivatives* / Q000037:antagonists & inhibitors; D002211:Capsaicin; D003371:Cough / Q000139:chemically induced / Q000503:physiopathology*; D003986:Dibenzocycloheptenes / Q000494:pharmacology; D016291:Dizocilpine Maleate; D008297:Male; D016202:N-Methylaspartate; D051381:Rats; D011919:Rats, Inbred Strains; D012018:Reflex / Q000187:drug effects*
D000927:Anticonvulsants; D003986:Dibenzocycloheptenes; D001224:Aspartic Acid; D016202:N-Methylaspartate; D016291:Dizocilpine Maleate; D002211:Capsaicin