This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Copyright Permission Citing Articles Citing Articles via Google Scholar Google Scholar Articles by DADA, M. O. Articles by BLAKE, C. A. Search for Related Content PubMed PubMed Citation Articles by DADA, M. O. Articles by BLAKE, C. A.

Effects of Neonatal Administration of Monosodium Glutamate on Somatotrophs and Growth Hormone Secretion in Prepubertal Male and Female Rats^*

Department of Anatomy, University of Nebraska Medical Center Omaha, Nebraska 68105
Department of and Physiology and Biophysics, University of Nebraska Medical Center Omaha, Nebraska 68105

Address requests for reprints to: Charles A. Blake, Ph.D., Department of Anatomy, University of Nebraska Medical Center, Omaha, Nebraska 68105.

Abstract

Female and male rats were injected with monosodium L-glutamate (MSG; 4 mg/g BW) or 0.9% saline as neonates and then decapitated on days 35 and 40 of life, respectively. Trunk blood was collected for RIA of serum GH. Anterior pituitary glands (APGs) were bisected. One half was assayed for GH. The other half was placed in culture medium to study the basal GH release rate. Pituitary sections from additional rats were stained for GH, and morphometric analyses were performed on the GH cells.

Treatment with MSG lowered serum GH levels and gland GH content in female but not in male rats. MSG did not alter the gland GH concentration or the basal GH release rate whether expressed per mg APG or per entire gland in either sex. The mean cross-sectional area of GH cells was reduced in either sex of MSG-treated rats. The numerical density of GH cells and the percentage of GH cells in APGs were similar in saline- and MSG-treated rats of either sex. The volume density of GH cells was lower in MSG-treated male rats only.

The results suggest that in prepubertal rats which had been given MSG as neonates 1) there is a sex difference in mean serum GH concentration and APG GH content, 2) GH cell size s i reduced in both sexes, and 3) the individual GH cells contain normal amounts of GH in spite of their smaller size. (Endocrinology 115: 996–1003, 1984)

Footnotes

^* This work was supported by grants from the NIH (HD-11011 and AM-19170) and the College of Medicine, University of Lagos, Lagos, Nigeria.

Received January 19, 1984.