Breitbart H, Rubinstein S
Department of Life Sciences, Bar-Ilan University, Ramat-Gan, Israel.
Arch Androl. 1988;20(3):229-35. doi: 10.3109/01485018808987077.
Plasma membranes isolated from ram spermatozoa contain calmodulin, which represents approximately 0.03% of the total sperm calmodulin and 0.025% of the membrane protein. When membranes were isolated in the presence of ethylene glycol (beta-aminoethyl ether) N,N,N',N'-tetraacetic acid (EGTA), the amount of calmodulin associated with the plasma membranes was reduced by only 20%. The ATP-dependent calcium transport activity of the isolated plasma membranes is not enhanced by adding calmodulin and not inhibited by the calmodulin antagonists trifluoperazinc (TFP), compound 48/80, or calmidazolium. In fact, there is an enhancement of calcium uptake by the calmodulin antagonists and this enhancement can be blocked by the Ca2+-channel blocker D-600. It is suggested that the ATP-dependent calcium transport activity in the plasma membrane of ram spermatozoa is not regulated by calmodulin.
从公羊精子中分离出的质膜含有钙调蛋白，其约占精子总钙调蛋白的0.03%，占膜蛋白的0.025%。当在乙二醇（β-氨基乙醚）N，N，N'，N'-四乙酸（EGTA）存在下分离膜时，与质膜相关的钙调蛋白量仅减少20%。分离出的质膜的ATP依赖性钙转运活性不会因添加钙调蛋白而增强，也不会被钙调蛋白拮抗剂三氟拉嗪（TFP）、化合物48/80或氯咪达唑抑制。事实上，钙调蛋白拮抗剂可增强钙摄取，且这种增强可被Ca2+通道阻滞剂D-600阻断。提示公羊精子质膜中的ATP依赖性钙转运活性不受钙调蛋白调节。
