Effects of eppikahangeto, a Kampo formula, and Ephedrae herba against citric acid-induced laryngeal cough in guinea pigs.
To evaluate the efficacy of three common antitussive Kampo formulas, eppikahangeto (EPP), bakumondoto (BAK), and shoseiryutogomakyokansekito (SGM), a new cough model of guinea pig was used, which could specifically induce a laryngeal cough by microinjection of citric acid solution into the larynx. Kampo extract was dissolved in water and the animals were given access ad libitum for 3 days, and then the number of coughs during 10 min was counted. EPP extract decreased the number of coughs dose-dependently (0.3% extract, -22.9 +/- 6.6%, P<0.01; 1.0% extract, -32.4 +/- 5.5%, P<0.01). BAK extract and SGM extract had no significant effect. Intraperitoneal injection of codeine (60 mg/kg) also decreased the number of coughs (-36.1 +/- 9.1%, P<0.05). Furthermore, Ephedrae herba (EH) extract reduced the number of coughs (-18.3 +/- 6.0%, P<0.05), but the extract of EPP without EH did not. These results suggest that EPP has an antitussive effect against laryngeally-induced cough in guinea pigs, and the crucial herbal medicine is EH.
Minamizawa
Kiyoshi
K
Department of Japanese Oriental Medicine, Faculty of Medicine, University of Toyama, Japan.
Goto
Hirozo
H
Shimada
Yutaka
Y
Terasawa
Katsutoshi
K
Haji
Akira
A
D000818:Animals; D000996:Antitussive Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D019343:Citric Acid; D003371:Cough / Q000139:chemically induced / Q000188:drug therapy* / Q000503:physiopathology; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D004353:Drug Evaluation, Preclinical; D029789:Ephedra / Q000737:chemistry*; D006168:Guinea Pigs; D007830:Larynx; D008297:Male; D008516:Medicine, Chinese Traditional; D020835:Medicine, Kampo; D008845:Microinjections; D010936:Plant Extracts / Q000302:isolation & purification / Q000627:therapeutic use*
D000996:Antitussive Agents; D010936:Plant Extracts; D019343:Citric Acid