Nutritional State and Catecholamine Metabolism in Macular Mice

Abstract

ABSTRACT Catecholamine and amino acid contents in the brain of the macular mutant mouse, a model mouse of Menkes kinky hair desease, were studied at days 4, 7, 10 and 13 postnatally. The contents of norepinephrine and epinephrine in the macular mutant mouse brain were significantly lower than those of controls at all ages. In contrast, the content of dopamine in the mutant mouse brain was significantly higher than that in the controls at days 4 and 7, and then it decreased rapidly to become less than that of age‐matched controls at days 10 and 13. Body weight gain of mutant mice was remarkably stunted, and weight loss was observed at day 7 of age. Body weight at day 13 postnatum was 56.1% that of the control. To examine the possible effects of malnutrition on the catecholamine metabolism in the mutant mouse brain, the contents of various amino acids in the brain and serum were measured. In the mutant mouse serum, tyrosine and phenylalanine, which play key roles in catecholamine metabolism, were significantly reduced compared to control, whereas only tyrosine showed a significant decrease in the brain. These results indicate that the rapid decrease in the catecholamine content in the macular mutant mouse brain is possibly influenced by the decrease in serum tyrosine subsequent to progressive malnutrition.