Spermatogenesis and sialic acid content and sialyltransferase activity in testis, epididymis and prostate of gossypol-treated male rats

Forty five-day-old male rats were fed for 14 weeks with gossypol acetic acid (15mg / kg b.w.). At dissection testis, epididymis and prostate were removed. Testis were examined histologically. In testis and pools of epididymis the content of sialic acid (SA) was estimated by the Warren's method. Testis, pools of epididymis and of prostate were examined for sialyltransferase (ST) activity by measurement of radioactivity incorporated into asialofetuin after incubation with CMP (¹⁴C sialic acid). The testicular weights of treated animals were similar to controls and spermatogenesis was normal. Following treatment, SA content in testis was significantly higher than in controls (1.70 ± 0.1 and 140 ± 9 versus 1.4 ± 0.1 μg/mg protein powder and 104 ± 16 μg/g wet tissue, correspondingly). Also in the epididymis there was a trend for higher amounts of SA after treatment: 3.3 ± 0.4 and 333 ± 31 versus 3.0 ± 0.3 μg/mg protein powder and 292 ± 51 μg/g wet tissue respectively. ST activity in testis and epididymis increased significantly after treatment (364946 ± 8343 and 207877 ± 24088 in comparison with 29520 ± 5767 cpm/167mg wet tissue and 148344 ± 2517 cpm/167mg wet tissue respectively). In the prostate an opposite trend was observed. It was assumed that gossypol treatment may interfere with glycoprotein and glycolipid synthesis.