Nakajyo S, Shimizu K, Kometani A, Kato K, Kamizaki J, Isogai A, Urakawa N
Jpn J Pharmacol. 1982 Feb;32(1):55-64. doi: 10.1254/jjp.32.55.
Bassianolide (BASS) is a cyclodepsipeptide isolated from cultured mycelia of Beauveria bassiana and is pathogenic to insects. In a longitudinal muscle preparation from guinea pig ileum, 10(-6) M BASS almost irreversibly inhibited an isotonic contraction induced by acetylcholine (ACH) and made the dose-response curve shift in parallel to the right (pA2: 7.6). It also inhibited the contractions induced by carbachol, pilocarpine, histamine, 5-hydroxytriptamine (5-HT) and prostaglandin E2, but did not inhibit the contraction induced by barium or a high concentration (40-60 mM) of potassium (high K). When applied to the guinea pig vas deferens, 10(-8) - 10(-7) M BASS inhibited an isometric contraction induced by norepinephrine (NE) (3 x 10(-6) - 10(-5) M), phenylephrine (3 x 10(-6) - 10(-5) M) or ACH (10(-6) - 10(-5) M). When the contractions of the three agonists exceeded the concentrations mentioned above, BASS failed to exert an inhibitory effect upon any of these agonists. It also inhibited the contraction caused by carbachol and histamine, but did not inhibit that induced by barium or high K. BASS itself failed to cause the contraction or relaxation of both muscle preparations. From these results, it is suggested that BASS inhibits the contraction induced by an agonist which acts upon selective sites of smooth muscle cells, but which does not inhibit a contraction induced by an agonist that has an effect on non-selective sites of cells.
蚕蛹虫草菌素（BASS）是一种从球孢白僵菌培养菌丝体中分离出的环缩肽，对昆虫具有致病性。在豚鼠回肠的纵肌标本中，10^(-6) M的BASS几乎不可逆地抑制了乙酰胆碱（ACH）诱导的等张收缩，并使剂量反应曲线平行右移（pA2：7.6）。它还抑制了卡巴胆碱、毛果芸香碱、组胺、5-羟色胺（5-HT）和前列腺素E2诱导的收缩，但不抑制钡或高浓度（40 - 60 mM）钾（高钾）诱导的收缩。当应用于豚鼠输精管时，10^(-8) - 10^(-7) M的BASS抑制了去甲肾上腺素（NE）（3×10^(-6) - 10^(-5) M）、去氧肾上腺素（3×10^(-6) - 10^(-5) M）或ACH（10^(-6) - 10^(-5) M）诱导的等长收缩。当三种激动剂的收缩超过上述浓度时，BASS对任何一种激动剂都没有抑制作用。它还抑制了卡巴胆碱和组胺引起的收缩，但不抑制钡或高钾诱导的收缩。BASS本身不会引起两种肌肉标本的收缩或舒张。从这些结果表明，BASS抑制了作用于平滑肌细胞选择性位点的激动剂诱导的收缩，但不抑制作用于细胞非选择性位点的激动剂诱导的收缩。
