Prilusky J, Deis R P
J Endocrinol. 1976 Jun;69(3):395-9. doi: 10.1677/joe.0.0690395.
The effect of prostaglandin F2 alpha (PGF2alpha) on milk ejection and on oxytocin release during suckling for one or two periods of 30 min was studied in lactating rats. Doses of PGF2 alpha (20 or 40 phi g) were injected i.p. 15 min before the suckling period. Control rats were injected with physiological saline. An inhibition of milk ejection proportional to the dose of drug administered was obtained. A normal milk ejection response was induced with a small dose of oxytocin injected immediately before nursing to mothers treated with PGF2 alpha, indicating that the blocking effect was not due to a lack of mammary gland response. Two groups of mothers were injected with 40 phi g PGF2 alpha 2 and 4 h respectively before suckling. In both groups milk ejection was partially but significantly inhibited. In rats pre-treated with sodium pentobarbitone (3-5 mg/100 g body wt) to prevent the release of oxytocin induced by suckling, PGF2 alpha (10 or 20 phi g) did not modify the inhibition of milk ejection indicating that PGF2 alpha does not have milk-ejecting activity. The administration of oxytocin to anaesthetized rats, immediately before a second suckling period, induced a normal milk-ejection response while in the rats treated with PGF2 alpha, oxytocin was less effective. The results indicate that PGF2 alpha inhibited milk ejection by a central block on oxytocin release and that the lipid is not able to mimic peripherally the milk-ejecting activity of oxytocin.
在泌乳大鼠中，研究了前列腺素F2α（PGF2α）对30分钟的一个或两个哺乳周期中排乳和催产素释放的影响。在哺乳前15分钟腹腔注射PGF2α（20或40μg）。对照大鼠注射生理盐水。获得了与给药剂量成比例的排乳抑制。在用PGF2α处理的母亲哺乳前立即注射小剂量催产素可诱导正常的排乳反应，这表明阻断作用不是由于乳腺缺乏反应。两组母亲分别在哺乳前2小时和4小时注射40μg PGF2α。在两组中，排乳均受到部分但显著的抑制。在用戊巴比妥钠（3 - 5mg/100g体重）预处理以防止哺乳诱导的催产素释放的大鼠中，PGF2α（10或20μg）并未改变排乳抑制，表明PGF2α不具有排乳活性。在第二次哺乳前立即向麻醉大鼠注射催产素可诱导正常的排乳反应，而在用PGF2α处理的大鼠中，催产素的效果较差。结果表明，PGF2α通过对催产素释放的中枢性阻断抑制排乳，并且该脂质不能在外周模拟催产素的排乳活性。
