The Golgi complex of the early spermatid in guinea pig.

After aldehyde-tannic fixation, Zinc-iodine-osmium fixation, Phospho Tungstic acid-chromium stain and two cytochemical reactions, the ultrastructure of the Golgi complex of early spermatids in the guinea pig reveals two different regions. One, close to the cell surface, involves endoplasmic reticulum (ER), intermediate vesicles, and Golgi outer cisternae and has membranes of uniform thickness and symmetrical trilaminar pattern, a strong ZIO precipitate, and an almost negligible cytochemical reaction to polysaccharides and cholesterol. The other region, close to the nucleus, exhibits thicker, sometimes asymmetric membranes, a polygonal network coating the thick cisterna, condensing vacuoles and areas of the acrosomal membrane, an intense reaction to polysaccharides and cholesterol, and packages of different densities in the condensing vacuoles and acrosome. This work also shows the coincidence of the cytochemical marker of cholesterol with the polygonal coating of clathrin in the condensing face of the Golgi.