Gans S E, McClintock M K
University of Chicago, Illinois 60637.
Horm Behav. 1993 Sep;27(3):403-17. doi: 10.1006/hbeh.1993.1030.
In young female rats, we found individual differences in LH surge characteristics that could underlie differences in fertility throughout adulthood and aging. We modified a jugular cannulation technique, which enabled us to characterize four successive proestrous LH surges in regularly cycling female rats. During a surge, the timing and amount of LH were negatively correlated, so that late-onset surges reached a low peak, late in the day. Within a female rat, the timing of the LH surge, but not the blood level of LH, was stable from cycle to cycle. Thus, differences in onset and peak time between successive LH surges within one female were less than differences among females. Moreover, these individual differences in timing of the LH surge were positively correlated with individual differences in lordosis reflex intensity on proestrus. Females with early-onset LH surges had high average lordosis reflex intensity on proestrus. Therefore, lordosis reflex intensity is a nonintrusive behavioral biomarker for individual differences in the timing of the preovulatory LH surge. This relationship between behavior and the preovulatory LH surge may reflect a hormonal basis for variations in reproductive strategies throughout the life span.
在年轻雌性大鼠中，我们发现促黄体生成素（LH）峰特征存在个体差异，这可能是成年期和衰老过程中生育能力差异的基础。我们改进了一种颈静脉插管技术，该技术使我们能够对正常发情周期的雌性大鼠连续四个动情前期的LH峰进行特征描述。在一次LH峰期间，LH的时间和量呈负相关，因此晚发的LH峰在当天晚些时候达到较低峰值。在一只雌性大鼠体内，LH峰的时间是稳定的，而LH的血液水平在不同周期间并不稳定。因此，一只雌性大鼠连续LH峰之间的起始时间和峰值时间差异小于不同雌性大鼠之间的差异。此外，LH峰时间的这些个体差异与动情前期的脊柱前凸反射强度的个体差异呈正相关。LH峰早发的雌性大鼠在动情前期的平均脊柱前凸反射强度较高。因此，脊柱前凸反射强度是排卵前LH峰时间个体差异的一种非侵入性行为生物标志物。行为与排卵前LH峰之间的这种关系可能反映了整个生命周期中生殖策略变化的激素基础。
