The Subcommissural Organ of the Vitamin B12-Deficient Rat

Abstract

Depleting the female rat of vitamin B₁₂ results in a significant incidence of hydrocephalus, subcutaneous edema and defects in organs including the kidney. A purified diet low in cobalt and vitamin B₁₂ resulted in a higher incidence of hydrocephalus than a practical type diet also low in cobalt and vitamin B₁₂. Reproduction was poor in females consuming the purified diet. This was attributed to increased food intake and moderate obesity in females consuming the purified diet. The subcommissural organ and certain periventricular and periaqueductal cells of the control newborn rat brain exhibited considerable quantities of stainable material positive to periodic acid-Schiff, chrome alum-hematoxylin, Gomori's aldehyde fuchsin, sulfhydryl and disulfide stains. Only insignificant amounts of the material were observed in brains of hydrocephalic animals but moderate quantities were present in littermates to hydrocephalics. Kidney damage seemed to vary directly with the degree of severity of hydrocephalus and edema. The possible relationship of the observed alterations in the vitamin B₁₂-deficient newborn to fluid dynamics was discussed.