替马西泮对豚鼠和大鼠离体气管平滑肌的松弛作用

Smooth muscle relaxant effects of tetrazepam on isolated guinea-pig and rat trachealis.

Herrera M D, Perez-Guerrero C, Marhuenda E

Laboratorio de Farmacología, Facultad de Farmacia, Universidad de Sevilla, Spain.

J Auton Pharmacol. 1996 Apr;16(2):105-10. doi: 10.1111/j.1474-8673.1996.tb00418.x.

Abstract

Tetrazepam (TZP) suppressed rat and guinea-pig tracheal tone by 100% and there was no difference in the relaxant effects against tone induced by 120 mM K+, carbachol (0.5 microM) or histamine (100 microM). 2. In trachealis pretreated with propranolol (1 microM), the relaxant response to TZP was unaltered. 3. TZP (10 microM) added to the relaxant effect of isoprenaline in tissues precontracted with carbachol. 4. The relaxant effect of TZP appears to be unrelated to peripheral benzodiazepine receptors (PBRs) because pretreatment with PK 11195 (1 microM) did not modify its effect. 5. Diltiazem (a calcium antagonist) was capable of relaxing the KCl (120 mM) or carbachol (0.5 microM) precontracted trachea, although at a different dose range than that of TZP. 6. The tracheal relaxation by TZP may be due to competition at some point in the chain of events linking carbachol, K+ or histamine to contraction, interacting with one of the transduction pathways, probably Ca2+. This inhibition of contraction is not related to the high-affinity PBRS.

摘要

替扎西泮（TZP）可使大鼠和豚鼠气管张力完全抑制，对由120 mM钾离子、卡巴胆碱（0.5微摩尔）或组胺（100微摩尔）诱导的张力的松弛作用无差异。2. 在预先用普萘洛尔（1微摩尔）处理的气管中，对TZP的松弛反应未改变。3. 在与卡巴胆碱预收缩的组织中，TZP（10微摩尔）增强了异丙肾上腺素的松弛作用。4. TZP的松弛作用似乎与外周苯二氮䓬受体（PBRs）无关，因为用PK 11195（1微摩尔）预处理并未改变其作用。5. 地尔硫䓬（一种钙拮抗剂）能够松弛由氯化钾（120 mM）或卡巴胆碱（0.5微摩尔）预收缩的气管，尽管其剂量范围与TZP不同。6. TZP引起的气管松弛可能是由于在将卡巴胆碱、钾离子或组胺与收缩联系起来的事件链中的某个点上存在竞争，与其中一种转导途径相互作用，可能是钙离子。这种对收缩的抑制与高亲和力PBRS无关。