The humoral immune response in marginally and severely magnesium deficient rats

Abstract

The effects of severe, moderate, and mild magnesium deficiencies on plasma proteins, immunoglobulin M (IgM), immunoglobulin G (IgG), and specific antibody response were studied. Forty male Sprague-Dawley rats were fed diets containing 50, 160, 280, and 400 μg magnesium/gram for either three or eight weeks. Eight of the rats were fed the control diet but were pair fed with the 50 μg/gram treatment group. All rats were immunized once with sheep red blood cells. Plasma magnesium levels reflected the dietary levels of magnesium, and bone magnesium highly correlated with plasma magnesium. The severely deficient rats had significantly enlarged spleens, while all other groups were similar to controls. The severe magnesium deficiency significantly decreased total plasma proteins. Additionally, immunoglobulin M and G levels were significantly reduced in the severely deficient rats. The mean log antibody titer for the severely deficient rats was approximately half that of the controls, but was not statistically different from the other dietary groups. Conversely, total plasma proteins were not lowered by the suboptimal levels of magnesium. Immunoglobulin M levels in the marginally deficient animals correlated with their plasma magnesium concentrations, and lower immunoglobulin G levels were found with the moderate magnesium deficiencies. Antibody response was not altered by the suboptimal levels of dietary magnesium.