Histochemical analysis of lizard testicular glycoconjugates during the annual spermatogenetic cycle.

The distribution of glycoconjugates in the testis of lizard Podarcis s. campestris De Betta was investigated by HRP-conjugated lectins during the annual spermatogenetic cycle. In addition, pretreatments of sections with neuraminidase and removal of alkali-labile O-linked sequences by beta-elimination allowed the structure of glycoconjugates to be further explored. Leydig cells displayed changes of lectin-binding sites during annual cycle, and during the abortive spermatogenesis period lacked N-linked sialylgalactosyl glycans. Sertoli cells stained by Con A, WGA, RCA120, BS I-B4, showed, except in July, O-linked sialylgalactosyl glycans. Spermatogonia bound Con A and WGA. Spermatocytes bound also BS I-B4, SBA, UEA I, and during spring spermatogenesis, revealed O-linked sialylgalactosyl glycans. The acrosomes of spermatids were also stained by RCA120 and PNA, whereas the heads of spermatozoa did not bind SBA and PNA. During the abortive spermatogenic period, the acrosomes showed O-linked sialylgalactosyl glycans and N-linked glycans terminating in beta-galactosyl residues. During the reproductive period, the acrosomes of spermatozoa expressed O- and N-linked sialylgalactosyl glycans and beta-galactosyl terminal residues on O- and N-linked glycans. This, in the testis of lizard, the two spermatogenesis periods show the emergence of different types of glycosylation.