Variations in the mast cell population of skin and bone marrow in magnesium-deprived rats. The influence of sex hormones.

Comparative counts of Alcian Blue-Basic Fuchsin-stained mast cells of the facial skin and bone marrow have been made in young rats of different sexes and strains, fed a diet deficient in magnesium (0.8 to 1 mg/100 g dry weight) for 4 weeks. Normal rats fed a magnesium-supplemented diet (65 mg/100 g dry weight) had about three times as many mast cells in the tibial metaphysis as in the facial skin. In both males and females fed the Mg-deficient diet, the marrow mast cells increased five to six times, while their number was concomitantly decreased in the skin. The marrow mast cells became also polymorphic, an indication of a possible preferential renewal site. Gonadectomy in the males had no effect on the above pattern. The administration of large doses of testosterone to males and estradiol to females depressed the mast cell population increase in the bone marrow and at the same time, moderated the loss of skin mast cells.