Ohmura I
Nihon Yakurigaku Zasshi. 1976 Mar;72(2):249-58.
Dibenamine (DB) produced contraction due to influx and release of Ca in normal medium, whereas it produced relaxation of the K-induced contraction due to depression of the activity of the muscle cell membrane. DB inhibited active influx, passive influx and release of Ca induced by ACh in this order as the concentrations were increased and also inhibited the contraction by histamine selectively as compared with the contractions by ACh, K and Ba, the inhibition of the ACh-, K- and Ba-contractions being almost to the same degree. In addition, DB inhibited to much the same degree the phasic contraction(PC) and tonic contraction(TC) by histamine, whereas it inhibited TC in preference to PC induced by ACh, K and Ba. Irreversible inhibition by DB of ACh-, K- and Ba-induced contractions were protected by Ca, whereas those of histamine-induced contraction were selectively protected by histamine and antihistamine, but not by Ca. These results indicate that the antagonism of DB and its irreversibility against histamine may be due to blockade of the histaminergic receptor, whereas those against ACh, K and Ba may be due to inhibition of the Ca-site. Evidence has been obtained suggesting that the irreversible parallel shift to the right of the log concentration-action curve of histamine after washout of DB may be due to spare receptors, whereas that of ACh, K or Ba may be due to inhibition of the Ca-site.
双苄胺（DB）在正常培养基中因钙离子内流和释放而产生收缩，而在钾离子诱导的收缩中，由于肌细胞膜活性受抑制而产生舒张。随着浓度增加，DB依次抑制乙酰胆碱（ACh）诱导的钙离子主动内流、被动内流和释放，并且与ACh、钾离子（K）和钡离子（Ba）诱导的收缩相比，DB选择性地抑制组胺诱导的收缩，对ACh、K和Ba诱导收缩的抑制程度几乎相同。此外，DB对组胺诱导的相性收缩（PC）和强直性收缩（TC）的抑制程度大致相同，而对ACh、K和Ba诱导的TC的抑制优先于PC。DB对ACh、K和Ba诱导收缩的不可逆抑制可被钙离子保护，而对组胺诱导收缩的不可逆抑制则被组胺和抗组胺药选择性保护，而非钙离子。这些结果表明，DB对组胺的拮抗作用及其不可逆性可能是由于组胺能受体的阻断，而对ACh、K和Ba的拮抗作用可能是由于对钙离子位点的抑制。有证据表明，洗脱DB后组胺对数浓度-作用曲线不可逆地平行右移可能是由于备用受体，而ACh、K或Ba的右移可能是由于钙离子位点的抑制。
