Botella A, Delvaux M, Fioramonti J, Frexinos J, Bueno L
Department of Pharmacology, INRA, Toulouse, France.
Eur J Pharmacol. 1993 Jun 11;237(1):131-7. doi: 10.1016/0014-2999(93)90102-n.
Isolated smooth muscle cells from the circular layer of pig and guinea-pig ileum were used to study the effect of prostaglandin E2 (PGE2) and three PGE2 receptor (EP) agonists; iloprost (EP1), butaprost (EP2) and enprostil (EP3). In pig cells, PGE2 and enprostil induced cell contraction (22.1 and 21.5% shortening of cell length, obtained at 10 nM for PGE2 and 1 nM for enprostil, respectively). Iloprost and butaprost had no contractile effect. However, the cholecystokinin octapeptide (CCK-8; 10 nM)-induced contraction was inhibited when cells were preincubated with iloprost or butaprost. In guinea-pig cells, PGE2, butaprost and iloprost induced cell contraction, whereas enprostil had no effect (23.1% for 10 nM PGE2, 22.8% for 1 nM butaprost and 22.6% for 10 nM iloprost). Preincubation with SC19220 (EP1 antagonist) inhibited the PGE2-, butaprost- and iloprost-induced contractions. When the contractile effect of PGE2, butaprost and iloprost was inhibited by addition of SC19220, these agents inhibited the cell contraction induced by CCK-8 (1 nM). Smooth muscle cells from guinea-pig and pig ileum express two PGE2 receptor subtypes that induce opposite effect. EP1 and EP3 receptors mediate cell contraction in guinea-pig and pig, respectively, whereas EP2 receptors mediate cell relaxation in both species.
从猪和豚鼠回肠环形肌层分离出的平滑肌细胞，用于研究前列腺素E2（PGE2）和三种PGE2受体（EP）激动剂的作用；依洛前列素（EP1）、布他前列素（EP2）和恩前列素（EP3）。在猪细胞中，PGE2和恩前列素诱导细胞收缩（细胞长度分别缩短22.1%和21.5%，PGE2在10 nM时获得，恩前列素在1 nM时获得）。依洛前列素和布他前列素没有收缩作用。然而，当细胞与依洛前列素或布他前列素预孵育时，胆囊收缩素八肽（CCK - 8；10 nM）诱导的收缩受到抑制。在豚鼠细胞中，PGE2、布他前列素和依洛前列素诱导细胞收缩，而恩前列素没有作用（10 nM PGE2时为23.1%，1 nM布他前列素时为22.8%，10 nM依洛前列素时为22.6%）。用SC19220（EP1拮抗剂）预孵育可抑制PGE2、布他前列素和依洛前列素诱导的收缩。当通过添加SC19220抑制PGE2、布他前列素和依洛前列素的收缩作用时，这些药物抑制了CCK - 8（1 nM）诱导的细胞收缩。豚鼠和猪回肠中的平滑肌细胞表达两种具有相反作用的PGE2受体亚型。EP1和EP3受体分别介导豚鼠和猪的细胞收缩，而EP2受体在两个物种中均介导细胞舒张。
