Miller A E, Riegle G D
J Gerontol. 1985 Mar;40(2):129-32. doi: 10.1093/geronj/40.2.129.
Concentrations of progesterone and luteinizing hormone (LH) were measured during the first diestrus and subsequent proestrus after constant estrous was interrupted by restraint stress. Stress stimulated an acute increase in serum progesterone. Although stress resulted in changes in vaginal cytology characteristic of normal estrous cycles, stress-treated constant estrous (CE) rats had no midcycle (diestrous day 1) elevation of progesterone and markedly lower LH and progesterone during the afternoon of proestrous than age-matched normally cycling controls. The majority of the treated rats resumed CE without completing a cycle. In a separate experiment, progesterone injection during proestrous resulted in increased LH secretion in aging rats with normal estrous cycles. These data indicate that decreased proestrous progesterone secretion may contribute to the decrease in neuro-endocrine stimulation of proestrous gonadotropin secretion in the aged rat and may be associated with the initiation of CE.
在持续发情被束缚应激打断后的第一个间情期和随后的发情前期，测定了孕酮和促黄体生成素（LH）的浓度。应激刺激血清孕酮急性升高。尽管应激导致了正常发情周期特征性的阴道细胞学变化，但应激处理的持续发情（CE）大鼠在间情期第1天没有孕酮的中期升高，且在发情前期下午的LH和孕酮明显低于年龄匹配的正常发情周期对照组。大多数处理过的大鼠恢复了持续发情，而没有完成一个完整周期。在另一个实验中，在发情前期注射孕酮导致正常发情周期的老龄大鼠LH分泌增加。这些数据表明，发情前期孕酮分泌减少可能导致老龄大鼠发情前期促性腺激素分泌的神经内分泌刺激减少，并且可能与持续发情的开始有关。
