Effect of Ca2+-channel blockers on isoprenaline-induced desensitization in rat trachea.
Isoprenaline-induced desensitization in vitro in rat trachea was studied in the presence of the Ca2+-channel blockers (Ca2+-CBs) verapamil and nitrendipine. The concentration-response curves for isoprenaline were determined in a noncumulative manner using carbachol as contracting agent, and then desensitization was achieved by 40-min incubation of the tracheal preparations with isoprenaline (1 microM). The effect of verapamil and nitrendipine was studied by the addition of each Ca2+-CB to the desensitizing solution. Both verapamil and nitrendipine reduced the isoprenaline-induced desensitization in the rat trachea.
Vassilev
P P
PP
Institute of Physiology, Bulgarian Academy of Sciences, Sofia.
D000818:Animals; D002121:Calcium Channel Blockers / Q000494:pharmacology*; D002217:Carbachol / Q000494:pharmacology; D066298:In Vitro Techniques; D007545:Isoproterenol / Q000494:pharmacology*; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects; D009126:Muscle Relaxation / Q000187:drug effects; D009568:Nitrendipine / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D014132:Trachea / Q000187:drug effects* / Q000502:physiology; D014700:Verapamil / Q000494:pharmacology*
D002121:Calcium Channel Blockers; D002217:Carbachol; D009568:Nitrendipine; D014700:Verapamil; D007545:Isoproterenol