Impact On Angiotensin â…¡-mediated Pressor Responses And Vessel Tone In Adult Offspring By High Sucrose Diets In Pregnancy And The Underlying Mechanisms

Objectives: To determine the influence of prenatal high sucrose diets on angiotensinII-mediated pressor responses and the underlying mechanism.Methods: Pregnant rats were provided with20%sucrose solution diets throughoutthe gestation. Blood pressure and vascular responses to angiotensin II were measured in5-month–old adult offspring. Currents of L-type Ca2+channels (Cav1.2) were measured insmooth muscle cells of small mesenteric arteries from the offspring.Results: Angiotensin II-mediated pressor responses were higher in the offspringexposed to prenatal high sugar than that of the control. In mesenteric arteries from the highsucrose offspring, AT1receptors, not AT2receptors, mediated the increasedvasoconstrictions; PKC antagonist GF109203X suppressed the angiotensin II-increasedvasoconstriction; PKC agonist phorbol12,13-dibutyrate produced greater contractileresponses, which were reversed by Cav1.2antagonist nifedipine. The expression of PKCαwas increased, while PKCδ unchanged; KCl-induced vasoconstriction was stronger, whichwas suppressed by nifedipine; nifedipine also reduced the enhanced vasoconstriction byangiotensin II. In addition, the Cav1.2of smooth muscle cells in mesenteric arteries fromthe high sucrose offspring showed larger current density, while its expression wasunchanged.Conclusion: The data suggest that high sucrose diets in pregnancy altered angiotensinII-mediated pressor responses and micro-vessel tone related to PKC/Cav1.2pathway in theoffspring, which could be partially attributed to altered AT1receptors, PKCα, and Cav1.2.