Hypervascularization of the cerebral cortex in lead-induced encephalopathy.

Pregnant rats were fed a diet containing 1.8% lead acetate for 8 days before delivery until the young were 3 month old. The density of the cerebral cortex capillaries of the infant rats and their convolution rate were studied morphometrically and noted to increase significantly according to the duration of lead treatment, as demonstrated by two-way analysis of variance. On the other hand, the thickness of the cortex reduced progressively. The increase of both capillary density and convolution rate is supposed to be related with this involution of cortex. This provides a quantitative insight of the previously described 'capillary activation' phenomenon, caused by lead encephalopathy and reveals it as a significant sequel of saturnine action.