Serio R, Mulè F, Adamo E B, Postorino A
Dipartimento di Biologia cellulare e dello Sviluppo, Università di Palermo, Italy.
Eur J Pharmacol. 1990 Jul 17;182(3):487-95. doi: 10.1016/0014-2999(90)90046-9.
The possible involvement of purines in the non-adrenergic non-cholinergic (NANC) relaxation of rat duodenum was studied using an isometric-isovolumic preparation. Purines (adenosine, AMP, ADP, ATP) induced a concentration-dependent, tetrodotoxin (TTX)-insensitive, fall in both endoluminal pressure and isometric tension. The relaxation induced by adenosine and by 2-chloroadenosine was selectively antagonized by 8-phenyltheophylline (1, 10 nM, 0.5 microM) and the ATP-induced relaxation was opposed by alpha, beta-methylene ATP (10 microM) and by reactive blue 2 (10 microM). Electrical field stimulation (EFS) caused TTX-sensitive inhibitory effects similar to those induced by ATP. None of the purinergic antagonists used were capable of affecting the EFS-induced relaxation. Our results indicate that both P1 and P2 purinoreceptors are present in muscle of the rat duodenum and are not involved in the NANC relaxation.
采用等长-等容标本研究了嘌呤在大鼠十二指肠非肾上腺素能非胆碱能（NANC）舒张中的可能作用。嘌呤（腺苷、AMP、ADP、ATP）引起管腔内压力和等长张力呈浓度依赖性、对河豚毒素（TTX）不敏感的下降。腺苷和2-氯腺苷诱导的舒张被8-苯基茶碱（1、10 nM、0.5 μM）选择性拮抗，ATP诱导的舒张被α,β-亚甲基ATP（10 μM）和活性蓝2（10 μM）对抗。电场刺激（EFS）引起与ATP诱导的类似的TTX敏感的抑制作用。所用的嘌呤能拮抗剂均不能影响EFS诱导的舒张。我们的结果表明，P1和P2嘌呤受体均存在于大鼠十二指肠肌中，且不参与NANC舒张。
