Effect of Vitamin A Intoxication on Intracranial Pressure and Brain Water in Rats1

GEORGIA W. MADDUX, FLOYD M. FOLTZ AND

STANLEY R. NELSON

ABSTRACT

Increased intracranial pressure occurs in both acute and chronic hypervitaminosis A in man, but a decreased cerebrospinal fluid (CSF) pressure has beenreported in various laboratory animals treated chronically with vitamin A. In order to clarify this difference in findings, measurements of brain water and CSF pressure were made in immature and mature rats treated with high doses of vitamin A. No pressure or brain water changes were observed in the acutely treated mature rats, but those treated chronically for 6 to 8 days had a 93% decrease in CSF pressure. Brain edema was also present in the treated animals; brain volume increased 2.0% in immature rats and 4.8% in mature rats. When the CSF pressure of chronically treated mature rats was raised to a normal CSF pressure by the addition of artificial CSF, their pressures dropped to near their opening pressure within 24 minutes. These data suggest that the decreased CSF pressure in rats given vitamin A is associated with an increased bulk absorption of CSF, probably due to pathological membrane or connective tissue changes. J. Nutr. 104: 478-482, 1974.