Palumbo M A, Salvestroni C, Gallo R, Guo A L, Genazzani A D, Artini P G, Petraglia F, Genazzani A R
Istituto di Clinica Ostetrica e Ginecologica, University of Pisa, Italy.
J Endocrinol Invest. 1995 Dec;18(11):853-6. doi: 10.1007/BF03349832.
Hippocampus plays an important role in cognition, neuroendocrine function and sexual behaviour. Changes of hippocampal neuropeptide and neurotransmitter concentrations are associated to behavioural changes occurring throughout reproductive life. The present study focused the attention on the presence of a neurosteroid, 5 alpha-pregnan-3 alpha-ol-20-one (termed allopregnanolone) in hippocampus. In particular, hippocampal allopregnanolone concentration in male and female prepubertal rats and in female rats throughout estrous cycle were evaluated. Hippocampal extracts were eluted on high pressure liquid chromatography and allopregnanolone concentration was measured by radioimmunoassay. Prepubertal male and female rats (15 days old) showed highest values which significantly decreased with advancing age (25 and 60 days) (p < 0.01); the lowest hippocampal concentration of allopregnanolone was found in adult rats. Female rats on proestrus morning and afternoon showed an hippocampal allopregnanolone concentration significantly higher than on diestrus or on estrus (p < 0.01), while rats on estrus showed hippocampal allopregnanolone concentration significantly lower than during other days of estrus cycle (p < 0.01). These data indicate differences in hippocampal concentration of allopregnanolone between prepubertal and adult rats and throughout estrous cycle in female rats. This finding suggest a putative role of neurosteroids in the modulation of behavioral changes occurring throughout reproductive life.
海马体在认知、神经内分泌功能及性行为中发挥着重要作用。海马体神经肽和神经递质浓度的变化与整个生殖生命周期中发生的行为变化相关。本研究聚焦于海马体中一种神经甾体5α-孕烷-3α-醇-20-酮（称为别孕烯醇酮）的存在情况。具体而言，评估了青春期前雄性和雌性大鼠以及处于发情周期的雌性大鼠海马体中别孕烯醇酮的浓度。海马体提取物通过高压液相色谱法洗脱，别孕烯醇酮浓度通过放射免疫分析法测定。青春期前的雄性和雌性大鼠（15日龄）显示出最高值，随着年龄增长（25日龄和60日龄）显著降低（p < 0.01）；成年大鼠海马体中别孕烯醇酮浓度最低。发情前期上午和下午的雌性大鼠海马体中别孕烯醇酮浓度显著高于间情期或发情期（p < 0.01），而发情期的大鼠海马体中别孕烯醇酮浓度显著低于发情周期的其他日子（p < 0.01）。这些数据表明青春期前和成年大鼠之间以及雌性大鼠发情周期中海马体别孕烯醇酮浓度存在差异。这一发现提示神经甾体在调节整个生殖生命周期中发生的行为变化方面可能发挥作用。
