抄録
We previously demonstrated the specific distribution of a calcium-dependent phospholipids binding protein, annexin 5, in the testis. As we found that annexin 5 was involved in gonadotropin secretion in the pituitary gonadotropes, it is hypothesized to be involved in some testicular function. To examine this possibility, in the present study, we studied first the effect of hemicastration and unilateral cryptorchidism on annexin 5 content and distribution in the testis. Effects of hCG, GnRH and testosterone on annexin 5 expression were also evaluated. Hemicastration increased annexin 5 content of the remaining testis after 24h. It was thought that this increase was induced by enhanced gonadotropin secretion after castration, because hCG (50 IU/head) augmented testicular content of annexin5 within 24h. It seemed that the interstitium was expanded with the augmentation of annexin 5 expression after hCG treatment. On the other hand, unilateral cryptorchidism also increased the annexin 5 expression of the cryptorchid testis during four weeks observation. Annexin 5 in the cryptorchid testis concentrated to intra-seminiferous tubules but not in the interstitium. The increase of testicular annexin 5 content seen after hemicastration and cryptochidism is thought to be induced by diverse mechanisms and in different cell species. Intratesticular administration of GnRH analog and subcutaneous testosterone injection both increased annexin 5 expression. These present data reveal multiple stimuli give changes in annexin 5 content in various cell species of the testis. Pituitary luteinizing hormone is suggested to augment annexin 5 synthesis in the interstitial cells.
