ULTRASTRUCTURAL-CHANGES IN THE SPERMATOZOA OF LANGUR MONKEYS PRESBYTIS-ENTELLUS ENTELLUS AFTER VAS OCCLUSION WITH STYRENE-MALEIC ANHYDRIDE

Changes in the physical characteristics of semen and ultrastructure of the spermatozoa of langur monkeys after vas occlusion with styrene ma leic anhydride (SMA), a polymer with PH-lowering action, are reported. Vas occlusion resulted in severe reversible hypospermia. Severe oligo spermia was observed in the majority of animals (five of eight) in the first ejaculation, 30 days after vas occlusion, and in two animals in the second ejaculation, 60 days after vas occlusion. Subsequent month ly ejaculations for 5 months revealed uniform azoospermia. The Voided spermatozoa were immotile and supravital staining confirmed necrosperm ia. Scanning electron microscopy (SEM) revealed severe coiling of tail , rupture of acrosomal envelope, and bent midpiece associated with dam aged mitochondrial sheath. Observations by transmission electron micro scopy (TEM) revealed vacuolization in the nucleus, membrane damage in the acrosome, loss of segmented columns, and numeric aberrations in th e centriole of the neck, as well as degeneration of mitochondrial shea th and axoneme in the midpiece, and absence of outer plasma membrane i n the midpiece and tail. The results indicate that the necrospermic st atus of the spermatozoa during initial ejaculations may offer instant sterility after vas occlusion with SMA. (C) 1998 Elsevier Science Inc. All rights reserved.