Ultrastructural changes in the testis and epididymis of rats following treatment with the benzene chromatographic fraction of the chloroform extract of the seeds of Carica papaya.

The benzene chromatographic fraction of the chloroform extract of the seeds of Carica papaya at a dose of 10 mg/rat/day for 150 days, which has shown a total inhibition of motility, reduced sperm count and infertility, was tested to de fi ne the mode of action at the subcellular level in the testis and epididymis. The ultrastructure of the testis of the treated animals revealed no appreciable changes in the subcellular characteristics. The mechanism of protein synthesis as well as steroidogenesis were evident in the Sertoli cells while the spermatogonia, spermatocytes and spermatids, both round and elongated, depicted a prominent nucleus, distinct nuclear membrane and cytoplasmic characteristics indicating normal germ cell differentiation. The principal cells of the cauda epididymis were characterized by the presence of well-de fi ned rough endoplasmic reticulum, mitochondria, Golgi bodies and secretary granules, suggesting active secretory functions. The absorptive function of the cauda epididymis was evidenced by the presence of numerous vesicles and multivesicular bodies adjacent to stereocilia. It is concluded that the inhibition of sperm motility by the drug could be due to other epididymal factors rather than the subcellular characteristics of testis and epididymis. Copyright 2004 John Wiley & Sons, Ltd.