Diekman M A, Anderson L L
Biol Reprod. 1982 Nov;27(4):827-32. doi: 10.1095/biolreprod27.4.827.
To determine whether pituitary receptors for estradiol-17 beta (E217beta) and progesterone (P4) change during prepubertal development, receptors were quantified by nuclear and cytoplasmic exchange assays from Yorkshire gilts 1, 2.5, 4, and 5.5 months old. No significant differences in the concentration of cytoplasmic or nuclear E217beta receptors were found during these prepubertal ages. Likewise, no differences in the concentration of cytoplasmic or nuclear P4 receptors were found during the four ages tested. These results suggest that prepubertal gilts approach the onset of puberty without a significant change in the concentration of E217beta or P4 receptors in the pituitary gland. To determine whether hypothalamic receptors for E217beta or P4 change during prepubertal development, receptors were quantified in hypothalami removed from these same gilts. At 2.5 months of age, the concentration of E217beta receptors was less (P less than 0.01), but the physiological significance of this reduction is unclear. No significant differences in the number of hypothalamic nuclear E217beta receptors were found during these prepubertal ages. Likewise, no differences in the concentration of cytoplasmic or nuclear P4 receptors were found during the four ages tested. These results suggest that prepubertal gilts approach the onset of puberty without an increase in the concentration of E217beta or P4 receptors in the hypothalamus.
为了确定在青春期前发育过程中垂体对17β-雌二醇（E217β）和孕酮（P4）的受体是否发生变化，通过核质交换试验对1、2.5、4和5.5月龄的约克夏母猪的受体进行了定量分析。在这些青春期前的年龄段，未发现细胞质或细胞核E217β受体浓度有显著差异。同样，在测试的四个年龄段中，细胞质或细胞核P4受体浓度也未发现差异。这些结果表明，青春期前的母猪在接近青春期开始时，垂体中E217β或P4受体的浓度没有显著变化。为了确定在青春期前发育过程中下丘脑对E217β或P4的受体是否发生变化，对从这些相同母猪身上取下的下丘脑的受体进行了定量分析。在2.5月龄时，E217β受体的浓度较低（P<0.01），但这种降低的生理意义尚不清楚。在这些青春期前的年龄段，下丘脑细胞核E217β受体的数量未发现显著差异。同样，在测试的四个年龄段中，细胞质或细胞核P4受体浓度也未发现差异。这些结果表明，青春期前的母猪在接近青春期开始时，下丘脑E217β或P4受体的浓度没有增加。
