Micropuncture and microanalytic studies of the effect of vasectomy on the rat testis and epididymis.

Micropuncture techniques adapted for in vivo use in the male reproductive tract were used to study the effect of vasectomy on the concentration and morphology of spermatozoa in the seminiferous tubules and ductus epididymidis of the rat. Regardless of surgical technique, 85% of all rats which had previously under vasectomy developed a speratic granuloma at the proximal end of the ligated vas deferens. Vasectomy did not affect the weights of the ipsilateral (vasectomized) testes. Vasectomy without granuloma formation resulted in an elevation in the weight of the ipsilateral epididymis and an increase in the concentration of spermatozoa in the ipsilateral cauda. Vasectomy complicated by granuloma formation caused a significant increase in the ratio of the spermatocrit in the seminiferous tubule to that in the caput. In the vasectomized rat without granuloma, significantly more abnormal spermatozoa were in the caput than in the cauda; in the normal rat, the concentrations of abnormal spermatozoa in the two regions were not significantly different. Vasectomies with and without granuloma formation are distinct phenomena and should be investigated separately.