Effects of Nanomolar to Submillimolar Carteolol on Noradrenaline Release in the Absence and Presence of Uptake_1 and Uptake_2 Blockers in Guinea Pig Pulmonary Arteries

概要

論文の詳細を見る
Effects of nanomolar to submillimolar carteolol, a non-selective β-antagonist, on the evoked release at 1 Hz and the spontaneous release in the absence and presence of uptake_1 and uptake_2 blockers were studied in pulmonary arteries, isolated from guinea pigs, and then preloaded with [^3H] noradrenaline. dl-Carteolol at 10^<-8>, 10^<-7> and 10^<-6> M applied at the increasing concentrations inhibited the evoked [^3H]-release in untreated arteries and in desipramine and corticosterone-treated arteries. The spontaneous [^3H]-release slightly but significantly increased or tended to increase in untreated arteries. dl-Carteolol at 10^<-5> and 10^<-4> M clearly and concentration-dependently increased the spontaneous [^3H]-release in untreated and cocaine-treated arteries. This increase was markedly inhibited by further pretreatment with normetanephrine. The evoked [^3H]-release was not altered by dl-carteolol at 10^<-5> M, but increased at 10^<-4> M. This increase was not modified by cocaine and by cocaine and normetanephrine. d-Carteolol at 10^<-5> and 10^<-4> M produced effects similar to those of dl-carteolol. Nanomolar to micromolar dl-carteolol inhibits the evoked [^3H]-release, which supports our previous conclusion that this inhibition is due to blockade of tonically functioning presynaptic β_2-adrenoceptors. Carteolol at the higher concentrations seems to become a substrate for an uptake_2 mechanism and to produce an unknown sympathomimetic activity in guinea pig pulmonary arteries.
公益社団法人日本薬学会の論文

Effects of Nanomolar to Submillimolar Carteolol on Noradrenaline Release in the Absence and Presence of Uptake_1 and Uptake_2 Blockers in Guinea Pig Pulmonary Arteries

スポンサーリンク

概要

著者

関連論文

スポンサーリンク