Golos T G, Sherwood O D
Endocrinology. 1984 Sep;115(3):1004-10. doi: 10.1210/endo-115-3-1004.
The role of the pituitary in regulating relaxin synthesis and secretion by the corpus luteum during the second half of pregnancy was investigated by hypophysectomizing rats carrying either one conceptus (1C) or a full complement (FC) of conceptuses (n greater than or equal to 8) on day 13 of pregnancy. Serum and luteal relaxin levels, serum progesterone levels, and luteal weights in 1C rats were markedly lower during the period from days 14 through 20 of pregnancy than those in FC rats, as has been previously reported. After hypophysectomy of 1C rats (H1C), serum relaxin levels, serum progesterone levels, and corpus luteum weights increased to values that were not significantly different from those of FC rats. Additionally, hypophysectomized FC rats (HFC) had higher serum relaxin levels than FC rats. Luteal relaxin content was unaffected by hypophysectomy in spite of increased relaxin secretion. Other workers have suggested that placental testosterone may support luteal function during the second half of pregnancy. Serum testosterone levels in 1C rats were markedly lower than those in FC rats, but did not increase after hypophysectomy in either H1C or HFC rats. It is concluded that the putuitary has a suppressive effect on relaxin secretion (and perhaps synthesis) as well as progesterone secretion and corpus luteum growth, and that increased luteal function after hypophysectomy is not due to increased placental testosterone secretion.
通过在妊娠第13天对怀有一个胚胎（1C）或完整胚胎（FC）（n≥8）的大鼠进行垂体切除，研究了垂体在妊娠后半期对黄体合成和分泌松弛素的调节作用。如先前报道，在妊娠第14天至20天期间，1C大鼠的血清和黄体松弛素水平、血清孕酮水平以及黄体重量均明显低于FC大鼠。1C大鼠垂体切除（H1C）后，血清松弛素水平、血清孕酮水平和黄体重量增加至与FC大鼠无显著差异的值。此外，垂体切除的FC大鼠（HFC）的血清松弛素水平高于FC大鼠。尽管松弛素分泌增加，但垂体切除对黄体松弛素含量无影响。其他研究人员认为，胎盘睾酮可能在妊娠后半期支持黄体功能。1C大鼠的血清睾酮水平明显低于FC大鼠，但在H1C或HFC大鼠垂体切除后均未升高。结论是，垂体对松弛素分泌（可能还有合成）以及孕酮分泌和黄体生长具有抑制作用，垂体切除后黄体功能增强并非由于胎盘睾酮分泌增加。
