Changes of Osmolarity of Brain, Cerebrospinal Fluid and Plasma in Acute Cytotoxic Edema in Cats

Abstract

The early cytotoxic type of ischemic edema is considered to be the consequence of two different pathological events. One is depolarization of cell membranes, resulting in intracellular uptake of sodium and water, and the other one is an increase in tissue osmolarity which also results in an uptake of water until equilibration with blood osmolality is reached {(Hossmann} 1976, Schuier 1980). The osmotically induced component of ischemic brain edema is of Particular interest because it may be affected by therapeutic manipulation of plasma osmolarity. In the present study spontaneous and induced changes of osmolarity of brain tissue, cerebrospinal fluid {(CSF)} and plasma were studied in focal cytotoxic edema and results obtained were correlated with cerebral blood flow {(CBF),} water and lactate content.