Zisapel N, Anis Y
Department of Biochemistry, George S. Wise Faculty of Life Sciences, Tel-Aviv University, Israel.
Mol Cell Endocrinol. 1988 Dec;60(2-3):119-26. doi: 10.1016/0303-7207(88)90170-0.
The effects of castration and subsequent testosterone and estradiol treatment and of a single injection of ethylene-1,2-dimethanesulphonate (EDS) on the distribution of [2-125I]iodomelatonin ([ 125I]melatonin) binding sites in the male rat brain were investigated. Castration produced a marked testosterone-reversible decrease in [125I]melatonin binding in the male rat brain, particularly in the hypothalamus and hippocampus. In contrast, [125I]melatonin binding in the parietal cortex, medulla-pons and cerebellum was generally unaffected by castration. Estradiol did not reverse the effect of castration on [125I]melatonin binding. A single injection of EDS which causes the destruction of Leydig cells led to a marked decrease in [125I]melatonin binding in the brain of the rats between 3 and 7 days after treatment. This decrease correlated with the decline in serum concentrations of testosterone. Specific [125I]melatonin binding and serum concentrations of testosterone subsequently increased to control levels within 37 days after treatment in accord with the repopulation of Leydig cells. The results clearly show that testosterone regulates the density of melatonin receptors in the hypothalamus and hippocampus of the male rat.
研究了去势以及随后给予睾酮和雌二醇治疗，还有单次注射乙烯 - 1,2 - 二甲磺酸酯（EDS）对雄性大鼠脑中[2 - 125I]碘褪黑素（[125I]褪黑素）结合位点分布的影响。去势导致雄性大鼠脑中[125I]褪黑素结合显著减少，且睾酮可使其逆转，尤其是在下丘脑和海马体中。相比之下，顶叶皮质、延髓 - 脑桥和小脑中的[125I]褪黑素结合通常不受去势影响。雌二醇不能逆转去势对[125I]褪黑素结合的影响。单次注射导致睾丸间质细胞破坏的EDS，在治疗后3至7天，大鼠脑中[125I]褪黑素结合显著减少。这种减少与血清睾酮浓度的下降相关。随着睾丸间质细胞的重新增殖，治疗后37天内，特异性[125I]褪黑素结合和血清睾酮浓度随后升至对照水平。结果清楚地表明，睾酮调节雄性大鼠下丘脑和海马体中褪黑素受体的密度。
