Hart I C, Morant S V
J Endocrinol. 1980 Mar;84(3):343-51. doi: 10.1677/joe.0.0840343.
Plasma concentrations of prolactin, growth hormone, insulin and thyroxine have been examined in relation to mammary growth and lactation induced by oestradiol benzoate (OB) and progesterone in ten virgin female goats. A daily injection of OB (250 microgram) and progesterone (60 mg) stimulated a significant, accumulative increase in prolactin in the circulation after 15 and 65 days and this was accompanied by udder growth. No increase in udder size was observed when prolactin was maintained at basal concentrations by simultaneous daily injections of the prolactin-inhibitor, bromocriptine (5 mg). Increasing the daily dose of OB (2.5 mg) and decreasing that of progesterone (6.25 mg) led to a further increase in both plasma prolactin and udder size and stimulated the onset of copious lactation. When prolactin was maintained close to basal concentrations throughout the periods of steroid treatment milk secretion was almost totally inhibited. There was some evidence that steroid treatment enhanced the prolactin response to milking and that additional quantities of bromocriptine were necessary to inhibit the secretion of prolactin when the pituitary gland was exposed to steroid stimulation. There were no marked changes in growth hormone, insulin or thyroxine in the circulation until the start of milking. It is concluded that the presence of increased quantities of prolactin in the blood are essential for the successful induction of mammary growth and lactation with OB and progesterone in virgin goats.
对10只未生育的雌性山羊，检测了血浆中催乳素、生长激素、胰岛素和甲状腺素的浓度，以研究它们与苯甲酸雌二醇（OB）和孕酮诱导的乳腺生长及泌乳的关系。每天注射OB（250微克）和孕酮（60毫克），15天和65天后可刺激循环中催乳素显著累积增加，同时伴有乳房生长。当通过每天同时注射催乳素抑制剂溴隐亭（5毫克）使催乳素维持在基础浓度时，未观察到乳房大小增加。增加OB的每日剂量（2.5毫克）并降低孕酮的剂量（6.25毫克），导致血浆催乳素和乳房大小进一步增加，并刺激大量泌乳开始。当在整个类固醇治疗期间催乳素维持在接近基础浓度时，乳汁分泌几乎完全受到抑制。有证据表明，类固醇治疗增强了催乳素对挤奶的反应，并且当垂体受到类固醇刺激时，需要额外剂量的溴隐亭来抑制催乳素的分泌。在开始挤奶前，循环中的生长激素、胰岛素或甲状腺素没有明显变化。结论是，血液中存在增加量的催乳素对于用OB和孕酮成功诱导未生育山羊的乳腺生长和泌乳至关重要。
