acid-phosphatase and Sarcocystosis

The present work is a sequel of our previous cytological investigations of the cyst-forming coccidia of the genus Sarcocystis (reported elsewhere), now performed on two species from different hosts: S. muris (mouse) and Sarcocystis sp. (water buffalo). Acid phosphatase is synthesized in the endoplasmic reticulum of cystic zoites, its activity being seen in particular in the microenemes. As was established earlier (Radchenko, 1991b), these organelles are extended regions of the smooth endoplasmic reticulum channels and are capable of separating from the latter to be aligned eventually along the pellicle of the parasite. Further on, micronemes are seen to attach to the inner membrane complex of the cystic zoites, so that the ductula of micronemes get into contact with the complex membranes. Just after this, the membranes are seen disassembled in the sites around this contact. The ductula of micronemes appear to be connected with the plasmalemma, i.e, the outer pellicle membrane, and protrusions of the plasmalemma appeared in the sites of these connections. Acid phosphatase (and presumably other substances contained in the micronemes) are poured into the plasmalemmal protrusions to form vesicles. In their turn, these vesicles are separated outside from the plasmalemma to move towards the sarcocyst subwall layer along the filamentous structures found in the septae of the sarcocyst ground substance. Then the membranes of the vesicles disappear, and phosphatase activity is observed in the cyst wall.

Topics: Acid Phosphatase; Animals; Biological Transport; Buffaloes; Glycoproteins; Heart; Histocytochemistry; Mice; Muscles; Proteoglycans; Sarcocystis; Sarcocystosis; Species Specificity