Tritrichomonas foetus: cytochemical visualization of the endoplasmic reticulum-Golgi complex and lipids.

The zinc iodide-osmium tetroxide technique was used to analyze the distribution of the endoplasmic reticulum-Golgi complex system of Tritrichomonas foetus. Interconnections between the cisternae of the endoplasmic reticulum as well as between cisternae of the Golgi complex were observed. The nuclear pores, as well as fenestrations in the Golgi complex, were evident. Three to four profiles of the endoplasmic reticulum were seen in the proximal marginal lamellae, related to the attachment of the recurrent flagellum to the protozoan body. No reaction product was seen in the costae, microtubules, glycogen particles, or hydrogenosomes. Imidazole-buffered osmium tetroxide solution was used to visualize lipids. Electron-dense materials were seen either free in the cytoplasm or within membrane-bounded cytoplasmic vesicles. A high contrast of some membranes, mainly of those which enclosed the hydrogenosomes, was observed in unstained sections.