Sharpe R M, Bartlett J M
J Reprod Fertil. 1985 May;74(1):223-36. doi: 10.1530/jrf.0.0740223.
Methods have been established and validated for quantitative assessment of the distribution of testosterone in the testis, by measurement of testosterone concentrations in whole testis, in isolated seminiferous tubules and in testicular interstitial fluid. These measurements were made in individual rats injected 2-40 h previously with saline (0.9% NaCl) or a potent antiserum to ovine LH. Testosterone concentrations in interstitial fluid and seminiferous tubules were closely correlated (r = +0.98; n = 60) and their relationship was log linear over a 200-fold range. However, although the concentrations of testosterone in interstitial fluid and seminiferous tubules decreased progressively with time after LH antiserum injection, this decrease was far more pronounced for interstitial fluid. In association with this change there was a significant increase in the amounts of a locally-produced factor in interstitial fluid which stimulates basal and hCG-stimulated testosterone production by isolated purified Leydig cells. This increase was reversed by injection of hCG but not by peripheral injection of a dose (20 mg) of testosterone propionate which restored normal intratesticular concentrations of testosterone. It is concluded that the tubular 'conservation' of testosterone, which occurs as interstitial fluid levels of this steroid decrease, may be a consequence of restricted diffusion of testosterone out of the tubules, but is also associated with increased amounts of a peptide stimulator of testosterone production.
通过测量整个睾丸、分离的生精小管和睾丸间质液中的睾酮浓度，已经建立并验证了定量评估睾丸中睾酮分布的方法。这些测量是在2至40小时前注射生理盐水（0.9% NaCl）或高效抗羊促黄体生成素血清的个体大鼠中进行的。间质液和生精小管中的睾酮浓度密切相关（r = +0.98；n = 60），并且它们在200倍范围内呈对数线性关系。然而，尽管注射促黄体生成素抗血清后，间质液和生精小管中的睾酮浓度随时间逐渐降低，但间质液中的降低更为明显。与此变化相关的是，间质液中一种局部产生的因子的量显著增加，该因子可刺激分离纯化的睾丸间质细胞的基础睾酮分泌和人绒毛膜促性腺激素刺激的睾酮分泌。注射人绒毛膜促性腺激素可逆转这种增加，但外周注射一剂（20 mg）丙酸睾酮恢复睾丸内正常睾酮浓度则不能逆转。结论是，随着该类固醇间质液水平降低而发生的睾酮的小管“保留”，可能是睾酮从管中扩散受限的结果，但也与睾酮分泌肽刺激物的量增加有关。
