ANTIHYPERTENSIVE EFFECT OF INTERLEUKIN-2 IN SALT-SENSITIVE DAHL RATS

We investigated the effects of interleukin-2, which stimulates the pro liferation and maturation of thymus-derived lymphocytes, on hypertensi on and organ injuries in genetically hypertensive rats. Interleukin-2 (5x10(4) U/kg body wt) was subcutaneously injected into Dahl salt-sens itive rats fed a 4% NaCl diet and spontaneously hypertensive rats once a week for 10 weeks. The effects on blood pressure, cardiovascular hy pertrophy, and renal function were evaluated. Interleukin-2 treatment lowered blood pressure in Dahl salt-sensitive rats (162 versus 187 mm Hg, P<.005). This antihypertensive effect was associated with an incre ase in glomerular filtration rate (589 versus 428 mL/d per 100 g body weight, P<.005) and reduction in cardiac weight (268 versus 305 mg/100 g body weight, P<.05). Interleukin-2 also alleviated the marked glome rular sclerosis in Dahl salt-sensitive rats (glomerular injury score, 151 versus 220; P<.001). in contrast, interleukin-2 did not affect the development of hypertension or organ injuries in spontaneously hypert ensive rats. Histologically, glomerular and arterial lesions of the ki dney were much less marked in spontaneously hypertensive rats than in Dahl salt-sensitive rats. These data indicate that interleukin-2 ameli orates the development of hypertension and cardiac and renal injuries in Dahl salt-sensitive (Hypertension.