Secretion of D-aspartic acid by the rat testis and its role in endocrinology of the testis and spermatogenesis
Secretion of D-aspartic acid by the rat testis and its role in endocrinology of the testis and spermatogenesis
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DOI：
10.1016/s0014-5793(98)01087-4
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发表时间：
1998-09-25
期刊：
影响因子：
3.5
通讯作者：
Setchell, BP
中科院分区：
文献类型：
--
作者：
D'Aniello, A;Di Fiore, MM;Setchell, BP
天冬氨酸的D-异构体(D-Asp)在大鼠睾丸中被发现。本研究收集了睾丸静脉血浆、睾丸网状液、间质细胞外液、曲细精管腔液、睾丸实质细胞、附睾精子和外周血浆两种方法，并用酶法和层析法对D-Asp进行了分析。这两种方法对所有样品的结果都非常相似。D-天冬氨酸在睾丸静脉血浆中浓度最高(约120nmol/ml)，在睾丸网液(95nmol/ml)和附睾精子(80nmol/g湿重)中浓度稍低。低水平仅见于睾丸实质细胞(主要由精子细胞和精母细胞组成)、生精小管腔腔液和间质细胞外液(分别为26、23和11nmol/ml)。但这些值均高于外周血浆(6nmol/ml)，说明D-Asp主要由睾丸分泌到静脉血中，然后进入睾丸网液，并在精子离开睾丸时或离开睾丸后进入精子内。因此，D-Asp的分布与睾酮有很大的不同。D-Asp在男性生殖道中的作用及其高浓度的原因尚不清楚。(C)1998年欧洲生化学会联合会。
The D-isomer of aspartic acid (D-Asp) has been found in rat testes. In the present study, samples of testicular venous blood plasma, rete testis fluid, interstitial extracellular fluid, luminal fluid from the seminiferous tubules, testicular parenchymal cells, epididymal spermatozoa and peripheral blood plasma were collected and analyzed for D-Asp by two methods, an enzymatic and a chromatographic HPLC method. The two methods gave very similar results for all samples. The highest concentrations of D-Asp (about 120 nmol/ml) were found in testicular venous blood plasma, with slightly lower concentrations in rete testis fluid (95 nmol/ml) and epididymal spermatozoa (80 nmol/g wet weight). Lower levels mere found in testicular parenchymal cells (which would comprise mostly spermatids and spermatocytes), luminal fluid from the seminiferous tubules and interstitial extracellular fluid (26, 23 and 11 nmol/ml respectively). However, these values were all higher than those for peripheral blood plasma (6 nmol/ml), It would appear that D-Asp is being secreted by the testis mostly into the venous blood, passing thence into the rete testis fluid and being incorporated into the spermatozoa at the time or after they leave the testis, The distribution of D-Asp is thus quite different from that of testosterone, and its role and the reason for its high concentration in the male reproductive tract remain to be elucidated. (C) 1998 Federation of European Biochemical Societies.