Morphological heterogeneity of peroxisomes in cultured mouse Leydig cells

Peroxisomes of different shapes were visualized in mouse Leydig cells from primary cultures by immunofluorescent demonstration of catalase and two peroxisomal lipid beta-oxidation enzymes, acyl-CoA oxidase and 3-ketoacyl-CoA thiolase. Apart from typical spherical profiles, rod-shaped, tubular and annular peroxisomes were also observed. The proportion between spherical and elongated forms varied from cell to cell; the latter forms seemed to occur more frequently in flattened cells spread on the glass in the course and after monolayer formation. On very rare occasions the Leydig cells contained small local networks of interconnected tubular peroxisomes, probably representing areas of peroxisomal reticulum, whose existence has been so far supported by substantial biochemical, but hardly any morphological evidence.