The Effects of Insulin on the Juxtaglomerular Apparatus and Plasma Renin Activity
In this study, the effects of insulin on plasma renin activity (RPA), serum sodium, potassium, and blood glucose levels in mice, and the histological and cytological changes occuring in the juxtaglomerular apparatus (JGA) are examined. After injection 250 U/kg of insulin into animals deprived of food overnight, we saw that the levels of blood glucose, sodium, and potassium decreased considerably while PRA levels increased. In the light and electron microscopic sections taken from these animals, the granules decreased in most of the juxtaglomerular granular cells. These cells have developed rough endoplasmic reticulum, increased polysomes, and multivesicular bodies. Granule distribution at various phases showed a noticeable difference in comparison with the control group. Sodium, potassium, and glucose levels decreased following injection of 20 U/kg insulin into animals on normal feeding programs for periods of 10 days, and more (30-60 days); the increase in PRA was unremarkable. The number of juxtaglomerular granular cells increased in JGA following injection of insulin over long periods (30-60 days). Electron micrographs have shown that this to be due to hyperplasia and metaplasia produced in both extramesangial cells and in the smooth muscle cells of the affrent arterioles.
DEMİRCİ, Cihan and ÖZARSLAN, Saime (1997) "The Effects of Insulin on the Juxtaglomerular Apparatus and Plasma Renin Activity," Turkish Journal of Biology: Vol. 21: No. 4, Article 5. Available at: https://journals.tubitak.gov.tr/biology/vol21/iss4/5