Plasma Levels Of Adrenomedullin,Atrial Natriuretic Perptide,Prostacyclin And Thromboxane A₂ In Descendants Of Parents With Essential Hypertension

Objective To study the plasma levels of ADM, ANP, PGI2 and TXA2 in descendants of parents with essential hypertension (EH) in search of the pathogenesis of EH and grounds for the primary prevention of EH.Methods 60 descendants, aged 26-40 years, of parents with essential hypertension were enrol led at random as study group which were divided into two subgroups: group 1 with 30 descendants of a parent with hypertension and group 2 with 30 ones of both parents with hypertension. Randomly recruited control group included 20 descendants of parents without hypertention. Plasma levels of ADM, ANP were determined by radioimmunoassay. Because TXA2 and PGI2 were unstable, plasma levels of their intermediates, TXB2 and 6-keto-PGFlalpha respectively, were detected instead.Results (1) In the study group, the concentrations of ADM and TXB2 were significantly elevated in comparison to those in the control group (t=2.22-7.35, P<0. 01). (2) Plasma level of 6-keto-PGFlalpha in the study group was significantly lower than that in the control group (t=2. 31-12. 67, P<0.01). (3) No significant difference in plasma level of ANP was found between the study and control group. (4) Between group 1 and group 2, the plasma concentrations of ADM, 6-keto-PGFlalpha elevated significantly (t=2.32; 13.08, P<0. 05;0. 01). Level of ANP had no significant change, while plasma level of TXB2 dropped significantly (t=8.97, P<0.05). (5) Plasma concentration of ADM was positively correlated with that of TXB2(r=0. 717, P<0. 01) and negatively correlated with that of 6-keto-PGFlalpha (r=-0. 819, P<0.01). (6) There was negative correlation between plasma levels of 6-keto-PGFlalpha and TXB2 (r=-0.857, P<0.01).Conclusions (1) Plasma levels of ADM, PGI2and TXA2 in descendants of parents with EH have already changed even though their blood pressure still remains normal. The disturbance of vasoactive substances is the precondition instead of the consequence of hypertension. (2) Altered vasoactive substances such as ADM, PGI2 and TXA2 reaches a new balance sothat blood pressure can keep normal. (3) The change of vasoactive substances such as ADM, PGI2 and TXA2 is hereditarily related and likely to be the pathogenesis of hypertension. (4) For descendants of parents with EH, shifted ADM, PGI2 and TXA2 can serve as predictors for the development of hypertention in the future.