Aortic vasoreactivity during a postnatal critical window of the pancreas in rats

Abstract

Changes in aortic vasoreactivity during the postnatal pancreatic critical window, where insulin and glucose, which modify vasoreactivity, are elevated, were studied and compared to those in control and metabolic syndrome (MS) rats. Twelve 21- and 28-day-old rats were used. To develop MS rats, male Wistar animals were given 30% sucrose in drinking water since weaning and used when 6 months old. Glucose and insulin levels were higher during suckling and decreased after weaning, and insulin and triglycerides levels increased in MS rats. Contraction elicited by norepinephrine (NE) was stronger than KCl contraction at all ages. KCl-induced contraction increased with, age being stronger in control rats; it further increased in MS rats. Norepinephrine-induced contraction increased from day 12 to day 28 but stabilized from day 21 to day 28; it was stronger in controls and increased in MS rats. Vasorelaxation to acetylcholine in NE precontracted rings did not change during the neonatal period, being similar to MS rats and lower than in controls. Insulin-induced increase in contraction elicited by KCl increased from day 12 to day 28 and increased from control to MS rats. There is a postnatal critical window in vasoreactivity that might predispose to cardiovascular diseases in adults.

Short-Term Exposure to High Sucrose Levels near Weaning Has a Similar Long-Lasting Effect on Hypertension as a Long-Term Exposure in Rats

“…A critical window of the pancreas has been described for this period and there are also important changes in plasma glucose and insulin at this stage [ 15 ]. Insulin and glucose modify adult arterial contractility [ 16 ] and we have previously described changes in arterial contractility during this critical window [ 17 ].…”

“…Metabolic syndrome (MS) rats that have hyperglycemia and hyperinsulinemia and hypertriglyceridemia have modified vasoreactivity [ 16 ]. We have also previously described changes in aortic contractility during this critical window lasting 16 days around weaning where plasmatic glucose and insulin concentrations vary [ 17 ].…”

High Sucrose Ingestion during a Critical Period of Vessel Development Promotes the Synthetic Phenotype of Vascular Smooth Muscle Cells and Modifies Vascular Contractility Leading to Hypertension in Adult Rats

“…These changes reflect endothelial dysfunction. There had been previous reports of enhanced contractility in rats with MS and in aortas in the presence of high insulin and glucose concentrations [ 45 ], and therefore, we previously studied the contractility of aortas during the CP of the pancreas where there are important changes in plasma concentrations of glucose and insulin [ 11 ]. Here, we analyzed the KCl- and NE-induced contractions.…”

“…During this stage, the natural rodent diet changes from rich in fat to rich in carbohydrates, and there is important maturation of the endocrine pancreas. This process is accompanied by changes in glucose and insulin concentrations, which may modify vascular responses, and the effects are due to changes in the endothelin-1 release and are mediated through the ET A and ET B receptors [ 10 , 11 ].…”

Metabolic Syndrome: Early Development and Aging

“…Hyperinsulinemia and insulin resistance are also present in rats which develop MS [61]. Changes in aortic vaso-reactivity during the postnatal pancreatic critical window, where insulin and glucose, are elevated have been studied and compared to those in control and MS rats [62].…”