Hart I C, Linzell J L
J Endocrinol. 1977 Feb;72(2):163-71. doi: 10.1677/joe.0.0720163.
Experiments to investigate the relative importance of the tactile, conditioned and possible metabolic components of the milking stimulus on the release of prolactin and growth hormone (GH) from the anterior pituitary of the goat are described. A comparison of the hormonal responses to milking the auto-transplanted mammary gland (i.e. denervated gland) with that obtained by milking the intact mammary gland of the same goat showed that the concentration of prolactin in the plasma increased only after milking the intact gland, whereas in two out of four goats an increase in plasma GH was detected several minutes after milking the transplanted gland. In the intact animal significantly more prolactin (P less than 0-01) was released in response to milking both teats for 6 min as compared with that released by milking only one teat for the same time. No significant difference (P less than 0-1) was found for GH. Similar quantities of prolactin and GH were released by goats milked when conscious or under anaesthesia. A comparison of the hormonal responses to teat stimulation in the same anaesthetized goats with and without the removal of milk from the mammary gland showed a significant reduction (P less than 0-001) in the quantity of prolactin and GH released in the absence of milk removal. The significance of these results is discussed.
本文描述了一些实验，旨在研究挤奶刺激中触觉、条件反射及可能的代谢成分对山羊垂体前叶释放催乳素和生长激素（GH）的相对重要性。将对自体移植乳腺（即去神经支配的乳腺）挤奶的激素反应与对同一只山羊完整乳腺挤奶的激素反应进行比较，结果显示，仅在对完整乳腺挤奶后，血浆中催乳素的浓度才会升高，而在四只山羊中有两只，对移植乳腺挤奶几分钟后，血浆GH水平就有所升高。在完整动物中，与同时只挤一只乳头6分钟相比，同时挤两只乳头6分钟后释放的催乳素显著更多（P<0.01）。对于GH，未发现显著差异（P<0.1）。清醒或麻醉状态下挤奶的山羊释放的催乳素和GH量相似。对同一麻醉山羊在有和没有从乳腺中挤奶的情况下乳头刺激的激素反应进行比较，结果显示，在不挤奶时释放的催乳素和GH量显著减少（P<0.001）。本文讨论了这些结果的意义。
