Morphofunctional evaluation of the adrenal gland in rats submitted to nutritional restriction during pregnancy

Abstract

Poor nutrition during pregnancy causes permanent metabolic and/or structural adaptation in offspring. The adrenal gland produces various steroid hormones during pregnancy. Thus, this study aimed to evaluate the influence of diet during pregnancy on the adrenal glands of Wistar rats. For this, 10-week-old pregnant Wistar rats (p, n=15) and non-pregnant rats (np, n=15) were divided into three groups and received a normoproteic control diet (C, 17% casein, n=5), isocaloric low-protein diet (PR, 6% casein, n=5), or 50% calorie restriction (CR, 50% of the diet consumed by group C), over a period of 21 days. On the 21st day of gestation (21dG, p groups) or on the 21st day of diet (np groups), after anesthetic deepening, the right adrenal gland was collected, weighed (total mass), and prepared for inclusion in Paraplast(R) for histomorphometric and immunohistochemical analysis (Ki-67, glucocorticoid receptors (GR), and mineralocorticoid receptor (MR)) in the different areas of the gland. Data, expressed as the mean {+/-} SD, were evaluated by one-way analysis of variance with Tukeys post-test (p < 0.05). CR in pregnancy increased the amount of GR, MR, and Ki-67 receptors in the adrenal gland. The npRC group showed highest GR staining compared to the animals that received a normal diet. Protein restriction in pregnancy decreases adrenal MR. The results allowed us to conclude that even without altering the weight of the adrenal glands, the pRC group suffered the most from stress during the study, suggesting that CR associated with pregnancy can cause morphofunctional changes in the adrenal glands.