Chronic lithium decreases blood pressure in spontaneously hypertensive rats

The effects of chronic lithium treatment on the blood pressure of spontaneously hypertensive rats were examined. Treated rats were fed a pelleted solid diet containing 1.696 g LiCl (40 mmol) /Kg diet. Control rats received a similar diet lacking the lithium. Rats were fed their respective diet for 21 days at which time intra-arterial blood pressure was recorded while the rats were conscious and freely moving. Lithium treated rats had a decreased systolic (20-30 mmHg) and mean (15-20 mmHg) arterial blood pressure as compared to the control spontaneously hypertensive rats. Heart rate was increased in the lithium treated group.