The reaction of capillaries isolated from rat brain to incubation with 10−4 M lead nitrate was investigated. Dense inclusions, probably containing lead, were found by electron microscopy inside most of the endothelial cell mitochondria. The steady‐state uptake of calcium by these cells was tripled after the exposure to lead. This increase may have been due in part to inhibition of active calcium efflux, since the adenosine triphosphate–dependent uptake of calcium by membranes prepared from the capillaries was abolished by 10−5 M Pb(NO3)2. In contrast, active uptake of potassium by the intact cells was not altered by lead. These results suggest that alterations in the calcium homeostasis of brain endothelial cells induced by the accumulation of lead may underlie the pathogenesis of brain edema in lead poisoning.
ASJC Scopus subject areas
- Clinical Neurology