Prolactin and Leydig cells: biphasic effects of prolactin on LH-, T3- and GH-induced testosterone/oestradiol secretion by Leydig cells in pubertal rats.
Prolactin and Leydig cells: biphasic effects of prolactin on LH-, T3- and GH-induced testosterone/oestradiol secretion by Leydig cells in pubertal rats.
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DOI：
10.1046/j.1365-2605.2001.00268.x
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发表时间：
2001-02
影响因子：
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通讯作者：
R. Maran;J. Arunakaran;M. M. Aruldhas-M.
中科院分区：
文献类型：
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作者：
R. Maran;J. Arunakaran;M. M. Aruldhas-M.
本文研究了大鼠催乳素（rPRL）对青春期大鼠Leydig细胞基础分泌及LH、GH和T3介导的睾酮和雌二醇分泌的影响。将纯化的Leydig细胞在37 ℃下在含有4%胎牛血清（FCS）的培养基中培养24小时。然后用含有不同浓度的rPRL（5-400 ng/mL）的新鲜培养基替换培养基，在34 ℃下在没有FCS的情况下培养48 h。rPRL在50-400 ng的剂量下增加Leydig细胞的睾酮分泌，并且在200 ng的剂量下观察到最大刺激。除了低剂量（5-50 ng/mL）外，雌二醇的分泌与睾酮的分泌平行。为了评估rPRL对LH、GH和T3诱导的间质细胞睾酮和雌二醇分泌的调节作用，将最小（50 ng）和最大（200 ng）有效剂量的rPRL与LH（25/100 ng）、GH（10/50 ng）和T3（25/50 ng）共同给药。rPRL（50/100 ng）与T3（25/50 ng）联合给药可降低睾酮分泌。虽然同时给予T3（25 ng）会减少rPRL诱导的雌二醇分泌，但在50 ng T3剂量下，后者没有改变。最低有效剂量的rPRL（50 ng）加LH（25 ng）刺激睾酮和雌二醇分泌。虽然最大有效剂量的rPRL（200 ng）不改变LH（25 ng）诱导的睾酮和雌二醇分泌，但它抑制100 ng LH诱导的睾酮分泌并增加雌二醇分泌。rPRL（50，200 ng）和GH（10/50 ng）的两个剂量抑制睾酮分泌相比，无论是GH或PRL单独诱导的睾酮分泌和刺激雌二醇分泌。目前的体外研究表明，rPRL刺激睾丸间质细胞分泌睾酮和雌二醇，这种作用可以通过LH，GH和T3调节。
The effect of rat prolactin (rPRL) on basal and LH-, GH- and T3-mediated testosterone and oestradiol secretion was studied in pubertal rat Leydig cells. Purified Leydig cells were cultured for 24 h at 37 degrees C in a medium containing 4% foetal calf serum (FCS). The medium was then replaced with fresh medium containing different concentrations of rPRL (5-400 ng/mL) for 48 h at 34 degrees C without FCS. rPRL increased testosterone secretion by Leydig cells at doses of 50-400 ng and maximum stimulation was observed at a dose of 200 ng. Oestradiol secretion was parallel to that of testosterone except at low doses (5-50 ng/mL). To assess the modulatory effect of rPRL on LH-, GH- and T3-induced Leydig cell testosterone and oestradiol secretion, minimum (50 ng) and maximum (200 ng) effective doses of rPRL were co-administered with LH (25/100 ng), GH (10/50 ng) and T3 (25/50 ng). Co-administration of rPRL (50/100 ng) with T3 (25/50 ng) decreased testosterone secretion. While co-administration of T3 (25 ng) decreased rPRL-induced oestradiol secretion, the latter was unaltered at a dose of 50 ng T3. A minimum effective dose of rPRL (50 ng) plus LH (25 ng) stimulated both testosterone and oestradiol secretion. While a maximum effective dose of rPRL (200 ng) did not alter LH (25 ng)-induced testosterone and oestradiol secretion, it inhibited testosterone secretion induced by 100 ng LH and increased oestradiol secretion. Both doses of rPRL (50, 200 ng) plus GH (10/50 ng) inhibited testosterone secretion when compared with testosterone secretion induced by either GH or PRL alone and stimulated oestradiol secretion. The present in vitro study indicates that rPRL stimulates both testosterone and oestradiol secretion by Leydig cells and that this effect can be modulated by LH, GH and T3.