Vasopressin has a direct effect on prolactin release in male rats.
Vasopressin has a direct effect on prolactin release in male rats.
复制标题
加压素对雄性大鼠催乳素的释放有直接影响。
作者：
S. Shin
在垂体后叶素（垂体后叶素的商业提取物）中发现了催乳素释放（PRF）活性。向植入永久性心房留置套管的清醒自由活动大鼠注射Pitressin，导致循环中催乳素浓度一过性升高。为了查明PRF活性是由于加压素还是由于加压素中未鉴定的组分，我们测试了合成赖氨酸加压素，并证明加压素（1 U/kg）使血浆催乳素浓度升高约3倍。相反，催产素（1 U/kg）没有改变催乳素浓度。为了确定加压素的作用是直接的还是间接的，我们测试了加压素对垂体切除大鼠的作用，该大鼠先前在肾包膜下植入了2个腺垂体。同样，该剂量（2 U/kg）的加压素升高循环血浆催乳素。这些实验表明，加压素可以提高循环催乳素浓度在非雌激素引发的正常雄性大鼠，加压素也刺激泌乳素分泌从直接下丘脑控制分离的移植腺体。
Prolactin-releasing (PRF) activity was found in Pitressin (a commercial extract from posterior pituitary for vasopressin). Injection of Pitressin into conscious free-moving rats implanted with a permanent atrial indwelling cannula, produced a transient increase in prolactin concentration in the circulation. In order to find out whether the PRF activity was due to vasopressin or to an unidentified component in the Pitressin, we tested synthetic lysine vasopressin and demonstrated that vasopressin (1 U/kg) elevated plasma prolactin concentration about threefold. In contrast, oxytocin (1 U/kg) did not alter the prolactin concentration. In order to find out whether the effect of vasopressin is a direct or indirect action, we tested the vasopressin effect on hypophysectomized rats which had previously been implanted with 2 adenohypophyses under the kidney capsule. Again this dose (2 U/kg) of vasopressin elevated circulating plasma prolactin. These experiments indicate that vasopressin can elevate circulating prolactin concentration in nonestrogen-primed normal male rats and that vasopressin also stimulates prolactin secretion from transplanted glands dissociated from direct hypothalamic control.