Electron Microscopic Study on the Effect of Alternate-Day Hydrocortisone Therapy on Lymphocyte Populations in Rat Spleen and Lymph Nodes

Abstract

The ultrastructural effects of 400 mg/M2/day of hydrocortisone sc, given alternatively from day 7 through day 19, were studied on the lymphocyte populations in the white pulp of the spleen and in the cortex of the mesenteric lymph nodes of the immunologically immature rat. Results were consistent with both a direct lytic effect of hydrocortisone on small lymphocytes of the nodular cortex of the mesenteric lymph nodes and an indirect effect on small lymphocytes of the periarterial lymphatic sheath (PALS) of the spleen supplied via the thymus. In contrast, medium-sized lymphocytes in the PALS appeared to be unaffected by hydrocortisone, while medium-sized lymphocytes of the nodular cortex of the mesenteric lymph nodes exhibited a temporary depletion of cytoplasmic organelles. Hydrocortisone appeared to depress protein synthesis in these latter cells. The decrease in numbers of lymphoblasts and plasmablasts observed in the nodular cortex of the mesenteric lymph nodes and the white pulp of the spleen is consistent with hydrocortisone interference with proliferation and differentiation of activated B cells.

Effect of long term Administration of hydrocortisone on some organs in females rats

“…In the present study there was severe atrophy of white pulp lymphoid tissue of spleen in high dose groups animals. Corticosteroid administration has long been known, to cause demolition of lymphoid tissues in certain adult animal species, including mice and rats, some clarified this due to the lytic effect of hydrocortisone apparent in small lymphocytes agreement with research in rats to EL-fouhil and Turkall, (1995). Treatment of mice with hydrocortisone decreased the number of thymus-cells to 6 per cent and the number of spleen-cells to 32 per cent of matched controls.…”