title: Special characteristics of the polar regions of the rat lens: morphology and phosphatase histochemistry.
abstract: Ultrastructural analyses of the normal rat lens revealed a number of characteristics present regionally within the anterior and posterior polar regions: (1) elaborate folding of the plasma membrane, including numerous microvillar processes; (2) wide intercellular spaces at basolateral cell borders; (3) concentrations of mitochondria; and (4) ouabain-sensitive Na-K-ATPase activity. These features, confined primarily to the suture systems and the anterior epithelium, suggested a cortical as well as an epithelial involvement in ion-linked fluid transport, supporting recent physiological investigations of the lens. Acid phosphatase localized in aggregations of smooth endoplasmic reticulum at the lens fiber ends suggested that this micro-organelle may be a source of acid hydrolases in the normal lens.
mesh_terms: D000135:Acid Phosphatase / Q000032:analysis*; D000818:Animals; D002462:Cell Membrane / Q000648:ultrastructure; D004721:Endoplasmic Reticulum / Q000032:analysis; D005260:Female; D006651:Histocytochemistry; D007908:Lens, Crystalline / Q000201:enzymology / Q000648:ultrastructure*; D008297:Male; D008928:Mitochondria / Q000648:ultrastructure; D051381:Rats; D000254:Sodium-Potassium-Exchanging ATPase / Q000032:analysis
chemical_list: D000135:Acid Phosphatase; D000254:Sodium-Potassium-Exchanging ATPase