Oral heparin prevents hypertension and elevated cytosolic calcium in salt-sensitive rats

This study examined the effect of oral heparin on systolic blood pressure, platelet cytosolic free calcium, aortic calcium uptake and renal vascular changes in Dahl salt-sensitive (DS) rats on low (0.4% NaCl) and high (8% NaCl) salt diet. Twenty-four male DS rats, age 8 weeks, were divided into four groups of 6 animals each. Groups I and II were on low salt diet and groups III and IV on the high salt diet. Additionally, groups I and III were placed on 100% H2O and groups II and IV on sodium heparin 0.5 mg/ml in H2O as their drinking water for a period of 6 weeks. At 14 weeks, systolic blood pressure, platelet cytosolic free calcium and aortic calcium uptake were significantly higher in rats on high salt diet and water compared with rats from all other groups. Oral heparin treatment prevented the increase in systolic blood pressure, platelet cytosolic free calcium and aortic calcium uptake in rats on high salt diet. Heparin also prevented or attenuated the onset of adverse renal vascular changes observed in Dahl salt-sensitive rats on high salt diet. Oral heparin treatment did not cause abnormal hematological, biochemical or pathological changes in rats.