冠脑益嗪(8205)可抑制豚鼠乳头状肌的收缩力,能降低其自律性,延长其不应期,而对兴奋性无明显影响。普诺洛尔和较大剂量的8205,均可使异丙肾上腺素的量-效曲线平行右移,符合竞争性拮抗剂的特点,唯8205的作用远弱于普诺洛尔;维拉帕米与8205,均可使CaCl_2的量-效曲线右移,且其最大收缩幅度,均有明显降低,呈非竞争性拮抗。 Cornellin (8205) can inhibit the contractility of guinea pig papillary muscles, can reduce their self-discipline, to extend its refractory period, while the excitability had no significant effect. Punctolol and the larger dose of 8205, can make the isoproterenol dose-response curve parallel shift to the right, in line with the characteristics of competitive antagonists, the only 8205 is far weaker than the effect of Puninolol; Vera Pa Both of rice and 8205 could make the volume-effect curve of CaCl_2 move to the right, and the maximal contractile amplitude of CaCl_2 decreased obviously, showing noncompetitive antagonism.