Relationship between Pituitary and Adipose Tissue after Hypothalamic Denervation in the Female Rat

Abstract

Neonatal administration of monosodium glutamate (MSG) to rats produces severe lesions in certain hypothalamic nuclei, with repercussions in different neuroendocrine axes, and serves as a model for their study. In addition, adipose tissue, as a target organ, is known to be directly related to several neurondocrine axes. We used 21-day-old female Sprague-Dawley rats that had received a neonatal treatment with MSG (4 mg/g body weight, i.p., from day 2 up to day 10 of age) in addition to control rats (injected with 10% NaCl solution, on a similar schedule). We performed a specific immunohistochemical study on each anterior-pituitary cell population, along with the morphometry of these cells and of the parietal and visceral adipose tissue, and measured the levels of serum leptin and triglycerides. The MSG animals evinced significant changes in volume density (VD), cell density (CD), and cell size (CS) in the corticotropes, thyrotropes, and LH gonadotropes, but not in the somatotropes, lactotropes, and FSH gonadotropes. The modification common to the three cell types was a hyperplasia, but with different results depending on cell size. Furthermore, in the MSG rats significant changes were also observed in the VD, CD, and CS of the adipose tissue, consisting of adipogenesis and decrease of adipocyte size in visceral fat, together with probable lipogenesis as judged by an increase in adipocyte size in the parietal fat. The serum levels of leptin and triglycerides appeared significantly higher in MSG animals. For the first time in this animal model, and at the level of three neuroendocrine axes, our results suggest changes that correlate hypothalamic damage, cellular pituitary alterations, and the response of the adipose tissue as a target organ for MSG insult.

Analysis of angiotensin II- and ACTH-driven mineralocorticoid functions and omental adiposity in a non-genetic, hyperadipose female rat phenotype

“…These measurements were recorded and processed automatically, and the following parameters were then calculated: volume density (VD = sum of adipocyte area/RA), cell density (CD = number of adipocytes/RA), and cellular size (CS; expressed in lm 2 ). As RA represents the total area were cells were scored, the division of the sum of the individual cell areas by the RA yielded VD, a parameter representing an estimate of cell mass according to generally accepted criteria [40]. The number of cells (CD) was calculated by dividing the immunostained area of the adipose tissue by the mean individual cell area.…”

Effect of Ethanol Extract of Red Beetroot (Beta vulgaris L.) on the Follicle Stimulating Hormone Levels among Wistar Rats (Rattus norvegicus) Exposed to Cigarette Smoke

“…Both of these hormones are necessary for the development of male and female gonads and are important for the processes of spermatogenesis and oogenesis. Disruption of the function of the hypothalamus may interfere with endocrine functions, including reproductive hormones, thereby affecting the process of folliculogenesis (Camihort, 2004) (Kumalasari, 2012). This study aims to prove whether the antioxidants found in beetroot can increase FSH levels in the ovarie of female white rats.…”

Pengaruh Vitamin C dan E terhadap Histologi Tuba Fallopii pada Tikus yang Dipapar MSG

“…MSG norvegicus) galur Wistar yang berjumlah 25 ekor yang juga secara nyata berpengaruh pada kerusakan telah sesuai dengan kriteria inklusi. hipotalamus dan hipofise dalam sekresi hormon yang Tempat penelitian dilakukan di Laboratorium Farmakologi berfungsi untuk perkembangan gonad pria dan wanita (2).…”