Effect of busulphan treatment and elevated temperature on the expression of the beta-pol gene in rat testis.

Changes in the expression pattern of the DNA polymerase beta gene during inhibition of spermatogenesis by busulphan and by temperature (artificial cryptorchidism) have been studied. Transient arrest of spermatogenesis in two-month-old rats after injection of a single dose of busulphan (10 mg/kg) resulted in parallel but transient decrease in the 1.4 kb of beta-pol mRNA level to an undetectable value, followed by its reappearance after resumption of spermatogenesis. An artificial cryptorchidism also caused a drastic decrease of beta-pol mRNA level. Both results as well as morphological examination of testis after busulphan injection and artificial cryptorchidism revealed that spermatocytes and spermatids represent the testicular cell fraction containing the elevated amount of beta-pol mRNA. Involvement of DNA polymerase beta in meiotic recombination is discussed.