DISSECTION OF WET TISSUE AND OF FREEZE-DRIED SECTIONS IN THE INVESTIGATION OF SEMINIFEROUS TUBULES AND INTERSTITIAL TISSUE FROM RAT TESTIS

Abstract

Seminiferous tubules and interstitial tissue were dissected out from freeze-dried sections and from wet tissues of the rat testis. The results of these preparation procedures were compared in regard to the distribution of a nonspecific esterase activity and of radioactive labeled steroids. Nonspecific esterase activity was found 50 times higher in interstitial tissue than in the seminiferous tubules, when samples disssected from wet tissue were analyzed. When specimens from freeze-dried sections were used for assays, this ratio was somewhat lower. In normal rat testes, the amount of interstitial tissue varied from 13 to 23%. The percentage of interstitium increased to about 50% in rats fed a diet lacking essential fatty acids. In seminiferous tubules isolated by the wet dissection technique there was no indication of the presence of interstitial tissue. Both fractionation procedures are useful in the analysis of enzyme activities, but the dry dissection method is preferable for studying the distribution of diffusible compounds, like steroids, because during wet dissection some redistribution of labeled steroids did occur.