DEGENERATIVE CHANGES IN SPERMATOGONIA ARE ASSOCIATED WITH LOSS OF GLUCOSE-TRANSPORTER (GLUT-3) IN ABDOMINAL TESTIS OF SURGICALLY INDUCED UNILATERAL CRYPTORCHIDISM IN RATS

Expression of facilitative glucose transporters (Glut 1, 2 and 3) was examined by Western blot analyses 10, 20 and 30 days following surgica lly induced unilateral abdominal cryptorchidism. The cryptorchid teste s exhibited marked degenerative changes in the seminiferous tubules an d spermatogonia, impaired and incomplete spermatogenesis and lack of s permatozoa in the lumen. Immunoblotting of testis proteins with Glut t ransporter antibodies revealed only the presence of Glut 2 and 3 prote ins. Glut 2 expression in abdominal testis was increased (45%, 67%, an d 40% at 10, 20 and 30 days, respectively) but no significant change w as observed in contralateral scrotal testis. Glut 3 expression was red uced by 85-95% compared with contralateral scrotal testis. A significa nt decrease in Glut 3 levels in abdominal testis was accompanied by an increase in scrotal testis Glut 3 content (80%, 144% and 212% at 10, 20 and 30 days, respectively) compared to age matched control rats. Th ese results suggested that the degenerative changes in abdominal testi s may be associated with decreased Glut 3 mediated glucose transport i n seminiferous tubules and spermatogonia. (C) 1997 Academic Press.