Infusion of angiotensin II at a slow pressor rate caused renal vasoconstriction and hypertension [18], which was prevented by deletion of the gene for TP receptors in the vascular smooth muscle cells [5], suggesting that the slow pressor dose of angiotensin II infusion could increase production of TXA2 and subsequently induce renal vasoconstriction [18, 19]. The gene discussed is AGT; the disease is Hypertension.