Whitely J, Willcox D L, Hartmann P E, Yamamoto S Y, Bryant-Greenwood G D
Biol Reprod. 1985 Oct;33(3):705-14. doi: 10.1095/biolreprod33.3.705.
Plasma relaxin levels were measured in animals at different stages of lactation and related to the amount of nuzzling and suckling behavior exhibited by the piglets. Only in some acute suckling episodes was relaxin secreted rapidly and episodically in spite of normal piglet and sow behavior and interaction. However, when the piglets were removed from the dams 6 h before suckling, the sows were very restless and the relaxin response to suckling was delayed. Oxytocin injection in lactating but nonsuckled sows caused an episodic secretion of relaxin similar to suckling itself. The source of relaxin in the lactating sow may be the old corpus luteum, since progesterone levels increased acutely, somewhat reflecting the profile of relaxin increase over the suckling episode.
在不同泌乳阶段的动物中测量了血浆松弛素水平，并将其与仔猪表现出的亲昵和吮乳行为量相关联。尽管仔猪和母猪的行为及互动正常，但仅在某些急性吮乳发作期间，松弛素才会快速且呈间歇性分泌。然而，当在吮乳前6小时将仔猪与母猪分开时，母猪会非常不安，并且对吮乳的松弛素反应会延迟。对处于泌乳期但未进行吮乳的母猪注射催产素会引起类似于吮乳本身的松弛素间歇性分泌。泌乳母猪体内松弛素的来源可能是旧黄体，因为孕酮水平急剧升高，在一定程度上反映了吮乳期间松弛素增加的情况。
