Bettini V, Calcagno A, Legrenzi E, Mayellaro F, Tomasi di Vignano F
Boll Soc Ital Biol Sper. 1982 Oct 30;58(20):1296-302.
The effect of external calcium concentration on the NE-induced contraction after beta-adrenergic blocking was studied in vitro. It resulted that the effect of NE was enhanced by increase, or reduced by decrease of calcium concentration. NE-induced contraction was not abolished when the bathing fluid was Ca++-free. The disappearance of the NE effect was only obtained in preparations treated with EDTA and perfused with Ca++-free Ringer-Locke solution. It is concluded that NE induced contraction after beta-adrenergic blocking is Ca++-dependent and on the tissue bound Ca++.
体外研究了β-肾上腺素能阻断后细胞外钙浓度对去甲肾上腺素（NE）诱导收缩的影响。结果表明，钙浓度升高可增强NE的作用，而钙浓度降低则使其作用减弱。当灌流液无Ca++时，NE诱导的收缩并未消除。只有在用乙二胺四乙酸（EDTA）处理并灌注无Ca++的林格-洛克溶液的标本中，NE的作用才会消失。结论是，β-肾上腺素能阻断后NE诱导的收缩依赖于Ca++，且依赖于组织结合钙。
