Sex-related differences in GH secretion in rat using reverse hemolytic plaque assay.
Sex-related differences in GH secretion in rat using reverse hemolytic plaque assay.
复制标题
使用反向溶血斑测定法观察大鼠 GH 分泌的性别相关差异。
DOI：
10.1152/ajpendo.1986.250.6.e650
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发表时间：
1986
期刊：
影响因子：
--
通讯作者：
Thorner,MO
中科院分区：
文献类型：
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作者：
Ho,KY;Leong,DA;Sinha,YN;Johnson,ML;Evans,WS;Thorner,MO
目前尚不清楚在男性中观察到的生长激素（GH）释放因子（GRF）刺激的生长激素释放是否反映了生长激素数量和/或对GRF的分泌反应的差异。我们解决了这个问题，通过使用溶血斑块测定，允许定量激素分泌单个垂体细胞。通过定量GH斑块形成细胞的百分比和测量斑块面积，比较了年龄匹配的雄性和发情第2天雌性大鼠的GRF-GH浓度-反应关系（0.01,0.1,1,10,100,1000 nM GRF）。男性垂体含有更高百分比的生长激素（斑块形成细胞百分比为45 +/- 2，女性为27 +/- 4%，平均+/- SE） （P < 0.05）。GRF诱导男性斑块面积的浓度依赖性增加。在10 nM GRF时，两性均达到最大反应。然而，男性的平均最大斑块面积显著大于（P < 0.001）， EC50显著低于（P < 0.05）（女性为0.25 +/- 0.09 nM，女性为1.78 +/- 0.64 nM）。这些数据表明，雄性中较大比例的生长激素以及较大的分泌能力和对GRF的敏感性可能导致了大鼠生长激素分泌的性别差异。
It is not known whether enhanced growth hormone (GH)-releasing factor (GRF)-stimulated GH release observed in the male reflects differences in somatotrope numbers and/or secretory response to GRF. We addressed this question by using the hemolytic plaque assay which allows quantification of hormone secretion by single pituitary cells. Time-course studies and GRF-GH concentration-response relationships (0.01, 0.1, 1, 10, 100, 1,000 nM GRF) in age-matched male and diestrous day 2 female rats were compared by quantitating the percent of GH plaque-forming cells, and measuring the plaque areas. The male pituitary contained a greater percent (P less than 0.05) of somatotropes (% of plaque-forming cells 45 +/- 2 vs. 27 +/- 4% in the female; mean +/- SE). GRF induced a greater concentration-dependent increase in plaque areas in the male. Maximal responses were attained at 10 nM GRF in both sexes. However, mean maximal plaque area was significantly greater (P less than 0.001) and the EC50 was significantly lower (P less than 0.05) in the male (0.25 +/- 0.09 vs. 1.78 +/- 0.64 nM in the female). The data suggest that the greater percent of somatotropes in the male and greater secretory capacity and sensitivity to GRF may contribute to sex-related differences in GH secretion in the rat.