The Leydig Cell in Health and Disease

Abstract

This chapter summarizes the morphological criteria to identify the fetal and adult Leydig cells in the rat testis at the light and electron microscopic levels. LH receptor and 3β-hydroxysteroid dehydrogenase are the most important functional markers that can be used to characterize the androgen-producing Leydig cells. The focus of this chapter is on the structure, ultrastructure, steroidogenic function, and ontogenesis of fetal and adult Leydig cells.