Testicular GnRH receptors--characterization and localization on interstitial tissue.
Testicular GnRH receptors--characterization and localization on interstitial tissue.
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睾丸 GnRH 受体——间质组织的表征和定位。
DOI：
10.1210/jcem-51-2-407
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发表时间：
1980
期刊：
影响因子：
--
通讯作者：
J. C. Marshall
中科院分区：
文献类型：
--
作者：
Gregory A. Bourne;S. Regiani;Anita H. Payne;J. C. Marshall
使用不可降解的GnRH类似物D-Ala 6des-Gly 10 GnRH乙基酰胺（D-Ala 6）作为配体，证明了睾丸GnRH膜受体。可置换125 I D-Ala 6结合存在于从整个睾丸和间质组织制备的粗膜上，但不存在于从曲细精管制备的组分上。125 I D-Ala 6与间质组织的结合是特异性的，因为只有未标记的D-Ala 6类似物和合成的GnRH抑制D-Ala 6示踪剂的结合。类似物数据的Scatchard分析揭示了单个高亲和力结合位点（Ka = 7 × 10（9）M-1），结合能力为200 +/- 10（SE）fmol/mg膜蛋白。用合成GnRH（每8小时6.6微克，持续3天）在体内处理完整和切除垂体的成年雄性大鼠，导致GnRH结合能力增加2倍，而受体亲和力没有变化。这些结果表明，特异性高亲和力GnRH受体仅存在于间质组织膜组分上，并且GnRH对睾丸的直接作用使受体数量增加。
Testicular GnRH membrane receptors were demonstrated using the non-degradable GnRH analog D-Ala6des-Gly10 GnRH ethylamide (D-Ala6) as ligand. Displaceable 125I D-Ala6 binding was present on crude membranes prepared from whole testes and interstitial tissue but not on the fractions from seminiferous tubules. 125I D-Ala6 binding to interstitial tissue was specific as only unlabeled D-Ala6 analog and synthetic GnRH inhibited binding of D-Ala6 tracer. Scatchard analysis of the analog data revealed a single high affinity binding site (Ka = 7 x 10(9) M-1) with a binding capacity of 200 +/- 10 (SE) fmol/mg membrane protein. In vivo treatment of both intact and hypophysectomized adult male rats with synthetic GnRH (6.6 microgram every 8 hr for 3 days) resulted in a 2-fold increase in GnRH binding capacity without change in receptor affinity. These results indicate that specific high affinity GnRH receptors are present only on interstitial tissue membrane fractions and receptor numbers are increased by a direct action of GnRH on the testis.