Abstract: Objective To observe the pathophysiological characteristics of adenosine A1 receptor (A1AR) gene knockout mice and to investigate the role of A1AR among renin secretion stimulated by low salt diet. Methods After A1AR+/- mice of C57BL/6J mating, multiplication and gene identification, offspring mice were used to experiments. The differences of following items between A1AR+/+ (n=13)and A1AR-/- (n=14)mice were observed: body weight, blood pressure, heart rate, renal function and electrolyte of serum and urine; Pathology features were observed after regular staining on kidney tissue samples. Renin expression at the kidney was stained by Immunohistochemistry. Plasma aldosterone level was also examined(A1AR+/+group, n=5 A1AR-/-group, n=5). Results After low salt diet, much higher renin expression of the kidney cortex and plasma aldosterone level were observed among A1AR-/- mice, accompanied with increasing of 24-hour urine potassium excretion (P<0.05). Conclusion A1AR may mediate the renin secretion stimulated by low salt diet in mice.

Key words: Low salt diet, A1AR, Renin