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 HighWire 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.

A Quantitative Immunocytochemical Study of the Luteinizing Hormone and Follicle-Stimulating Hormone Cells in the Adenohypophysis of Adult Male Rats and Adult Female Rats throughout the Estrous Cycle^*

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

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

Abstract

We investigated whether 1) the absolute or the relative numbers of LH and FSH cells change during the rat estrous cycle, 2) the percentages of gonadotrophs that contain LH and/or FSH change during the estrous cycle, and 3) gonadotrophs change in size during the rat estrous cycle.

Groups of four female rats were decapitated at one of five different times during the estrous cycle. Four male rats were also decapitated. Serum concentrations of LH and FSH were determined by RIA. Paired horizontal flip-flopped or nonflipped paraffin sections were mounted from the dorsal, middle, and ventral portions of each pituitary gland. In each pair of sections, one was stained with a-rat LH-S4 and the other with a-rat FSHS7 by the unlabeled antibody peroxidase-antiperoxidase method. All immunoreactive cells were counted. Photographs were taken from randomly chosen corresponding areas, and the cells were individually matched to determine the percentage that contained one or both hormones. Correction factors had to be used because in paired flip-flopped or nonflipped sections stained with the same antibody (a-rat LH-S4), not all of the stained cells found in one section were found in the other section.

The absolute numbers of LH and FSH cells did not change throughout the estrous cycle. The ratio of LH cells to FSH cells in the pars distalis of female rats was also constant throughout the estrous cycle. In female rats, 75.2% of LH cells also contained FSH, while 99.4% of FSH cells also contained LH. In the male rats, 88.6% of LH cells also contained FSH, while 98.6% of FSH cells also contained LH. Similar results were obtained in paired flip-flopped sections stained with a-rat LHβ and a-rat FSHβ.

Sequential staining of additional individual tissue sections with a-rat LH-S4 and then a-rat FHS-S7 or vice versa revealed the following. Staining of LH-stained tissue for FSH revealed less than 1% new cells, but staining of FSH-stained tissue for LH revealed a 8.7% increase in gonadotrophs in males and a 25.4% increase in females. The gonadotrophs in female rats did not change in size during the estrous cycle and were significantly smaller than the gonadotrophs in male rats.

The results suggest that in normal adult rats: 1) virtually all FSH-containing cells contain LH, 2) about 25% of the gonadotrophs in females and about 11% of the gonadotrophs in males contain LH but not FSH, 3) the number of cells containing LH or those containing LH and FSH does not change during the estrous cycle, 4) gonadotrophs in female rats do not change in size during the estrous cycle and are smaller than the gonadotrophs in male rats, and 5) FSH release during the early morning of estrus, when the serum FSH concentration is elevated and the serum LH concentration is low, occurs from cells that contain both LH and FSH. (Endocrinology 113: 970, 1983)

Footnotes

^* Address requests for reprints to: Dr. Charles A. Blake, Department of Anatomy, University of Nebraska Medical Center, 42nd Street and Dewey Avenue, Omaha, Nebraska 68105.

Received December 20, 1982.

This article has been cited by other articles:

				J L Crawford, D A Heath, L J Haydon, B P Thomson, and D C Eckery Gene expression and secretion of LH and FSH in relation to gene expression of GnRH receptors in the brushtail possum (Trichosurus vulpecula) demonstrates highly conserved mechanisms Reproduction, January 1, 2009; 137(1): 129 - 140. [Abstract] [Full Text] [PDF]

				A Tury, G Mairet-Coello, F Poncet, C Jacquemard, P Y Risold, D Fellmann, and B Griffond QSOX sulfhydryl oxidase in rat adenohypophysis: localization and regulation by estrogens J. Endocrinol., November 1, 2004; 183(2): 353 - 363. [Abstract] [Full Text] [PDF]

				N. A. Mitchner, C. Garlick, and N. Ben-Jonathan Cellular Distribution and Gene Regulation of Estrogen Receptors {alpha} and {beta} in the Rat Pituitary Gland Endocrinology, September 1, 1998; 139(9): 3976 - 3983. [Abstract] [Full Text] [PDF]