Angiotensin II-mediated vascular changes in aged offspring rats exposed to perinatal nicotine

Abstract

This study determined the long-term influence of prenatal nicotine exposure (PN) on blood pressure and vascular functions in the aged offspring rats. PN did not affect body weight and plasma adrenocorticotropic hormone level; however, it significantly reduced plasma angiotensin I and angiotensin II in both sexes. Systolic pressure in the male aged PN offspring was significantly higher. Angiotensin II-increased mean arterial pressure was higher in the aged PN offspring than that in the control regardless of sex. AT1 receptor blocker losartan, not AT2 receptor antagonist PD123319, reduced blood pressure in the aged PN rats more than that in the control. In the aged PN offspring, angiotensin II-increased vessel contraction and intracellular calcium level were higher in small mesenteric arteries. Acetylcholine-mediated vascular relaxation was weaker, and nitric oxide-related endothelial functions were damaged in aortic rings of PN offspring. Thickness of the wall of mesenteric arteries was increased in the male aged PN offspring. Ratio of AT1/AT2 receptors was significantly increased in the vessel of the PN group regardless of sex. These data provide new information on the very long term influence of PN on vascular structures and functions in the aged offspring, demonstrate that the aged PN female rats were not free of vascular risks after menopause, and suggest that multiple pathways may be involved in the detrimental alterations of the cardiovascular system of the PN rats.