Franklin R B, Brandly R L, Costello L C
Prostate. 1982;3(6):637-42. doi: 10.1002/pros.2990030614.
The prostate gland is unusual in that it has a high content of citric acid compared with other soft tissues. The mechanism of citrate accumulation in prostate is unknown. One possibility is that aspartate aminotransferase (AAT) could supply an extra Krebs cycle source of oxaloacetate for citrate formation. Since testosterone regulates citrate production and secretion and strong transaminase activity exists in prostate, a relationship between AAT and citrate production could exist if testosterone also regulates AAT activity. To investigate this possibility, animals were castrated and given testosterone. After a total castration period of 72 hours, animals were sacrificed and mitochondrial AAT activity determined. Results revealed that castration decreased AAT activity and testosterone replacement stimulated activity. Neither castration nor testosterone affected malate dehydrogenase (MDH) activity. Both actinomycin D and cycloheximide blocked the testosterone stimulation of AAT activity. These studies indicate that testosterone may regulate AAT activity in rat ventral prostate. Furthermore, regulation may occur through testosterone stimulation of specific RNA and protein synthesis.
前列腺不同寻常之处在于，与其他软组织相比，它含有高浓度的柠檬酸。前列腺中柠檬酸盐积累的机制尚不清楚。一种可能性是，天冬氨酸氨基转移酶（AAT）可为柠檬酸形成提供额外的三羧酸循环草酰乙酸来源。由于睾酮调节柠檬酸的产生和分泌，且前列腺中存在强大的转氨酶活性，如果睾酮也调节AAT活性，那么AAT与柠檬酸产生之间可能存在关联。为了研究这种可能性，对动物进行阉割并给予睾酮。在总共72小时的阉割期后，处死动物并测定线粒体AAT活性。结果显示，阉割降低了AAT活性，而睾酮替代则刺激了活性。阉割和睾酮均未影响苹果酸脱氢酶（MDH）活性。放线菌素D和环己酰亚胺均阻断了睾酮对AAT活性的刺激。这些研究表明，睾酮可能调节大鼠腹侧前列腺中的AAT活性。此外，调节可能通过睾酮刺激特定的RNA和蛋白质合成来实现。
