Hypotensive action of OPC-1427, a new beta-adrenergic blocking agent in rats.

8-Acetonyloxy-5-[3-(2-(3,4-dimethoxyphenyl)-ethylamino)-2-hydroxypropoxyl]-3,4-dihydrocarbostyril (OPC-1427), is a newly synthesized cardioselective beta-adrenoceptor blocking agent and we examined the effects of this compound given intraperitoneally to consious Kyoto Wistar normotensive (WKR), spontaneous hypertensive (SHR) and DOCA-NCl hypertensive (DOCA rat) rats. The results were compared to findings with propranolol and practolol. OPC-1427 produced a significant hypotensive action in SHR and DOCA rats and this effect was less in WKR. With propranolol and practolol effective hypotensive effects were seen in WKR and DOCA rats but not in the SHR. The efficacy of the hypotensive action of these agents was propranolol greater than OPC-1427 = practolol in WKR, OPC-1427 greater than practolol in SHR, and OPC-1427 greater than practolol = propranolol in DOCA rats. Thus OPC-1427 appears to be a promising beta-adrenoceptor blocking agent which exerts a hypotensive state, as demonstrated in hypertensive rats.