Enhancement of pharmacologically induced bronchoconstriction by Ro 5-4864.
Pretreatment with Ro 5-4864 enhanced the bronchoconstrictor responses to histamine or carbachol in the anaesthetized artificially ventilated guinea pig. This suggests the involvement of a peripheral-type benzodiazepine receptor as also indicated by the lack of effect of clonazepam. PK 11195 did not antagonize the Ro 5-4864-induced enhancement, but itself enhanced the bronchoconstrictor responses to histamine or carbachol. The data indicate that Ro 5-4864 and PK 11195 behave as metactoid sensitizers of histamine or carbachol.
Marano
G
G
Laboratorio di Farmacologia, Instituto Superiore di Sanità, Roma, Italy.
Massotti
M
M
Spagnolo
A
A
Carpi
A
A
D000818:Animals; D001570:Benzodiazepinones / Q000494:pharmacology*; D001980:Bronchi / Q000187:drug effects*; D002217:Carbachol / Q000494:pharmacology*; D004357:Drug Synergism; D006168:Guinea Pigs; D006632:Histamine / Q000494:pharmacology*; D007275:Injections, Intravenous; D008297:Male; D012121:Respiration, Artificial
D001570:Benzodiazepinones; C028513:4'-chlorodiazepam; D006632:Histamine; D002217:Carbachol