Expression and immunolocalisation of follicle-stimulating hormone receptors in gonads of newborn and adult female horses

Abstract

In mares, FSH and its receptor (FSHR) are essential for ovarian function. The objective of the present study was to analyse FSHR gene expression at the mRNA and protein levels in ovarian tissue from newborn and adult horses. Expression of mRNA was analysed by reverse transcription polymerase chain reaction, whereas FSHR protein was visualised by immunohistochemistry (IHC), immunofluorescence labelling (IF) and western blot. FSHR mRNA was detected in ovarian follicles and luteal tissue from adult mares, as well as in the ovaries of neonates. Follicular growth up to 4mm in diameter was already present in neonates. Using IHC and IF, FSHR protein was detected in granulosa cells, cumulus cells and inconsistently in oocytes, independent of the animal's age or the stage of folliculogenesis. A lower FSHR expression was observed in theca cells in comparison to granulosa cells. FSHR was abundant in the ovarian stroma cells of neonates but not of adults. Luteal cells stained positive for FSHR independent of the stage of corpus luteum development. The presence of FSHR protein in various cell populations of the ovary was confirmed by western blot. In conclusion, FSHR is present in horse ovaries consistently from birth onwards and expression remains constant during the oestrous cycle.

Expression and localisation of FSHR, GHR and LHR in different tissues and reproductive organs of female yaks

“…However, animal studies showed that the FSHR is present in horse ovaries constantly from birth, throughout life, and expressed in the oestrous cycle. FSHR protein was found in granulosa cells, cumulus cells and inconsistently in oocytes, independent of animal age or folliculogenesis stage [19]. However, this test demonstrated that the main locations of FSHR/GHR/LHR were in muscular layer and intima of uterus, mucous membrane of oviduct, granulosa cells of ovary.…”

In vivo antral follicle wall biopsy: a new research technique to study ovarian function at the cellular and molecular levels

“…The recent progress in molecular biology techniques has brought a new perspective to our knowledge in the area of mammalian folliculogenesis. Previous studies in livestock animals used antral follicles that were obtained from abattoirs, ovariectomy, or euthanasia [ 9 – 19 ]. Although those ovarian sources provide sufficient materials for various molecular biology techniques, follow-up studies are either impossible or potentially jeopardize animals’ fertility.…”

Effects of Matricaria chamomilla Extract on Growth and Maturation of Isolated Mouse Ovarian Follicles in a Three-dimensional Culture System

“…[ 31 ] Structurally, it is a G protein-coupled and seven-transmembrane receptor which links to the several pathways, such as adenylate cyclase. [ 32 ] It has been reported that the FSHR is expressed in growing follicles. [ 32 ] PCNA is a protein with a weight of 36,000 and it has been reported in fetal and adult ovaries of several mammals.…”

“…[ 32 ] It has been reported that the FSHR is expressed in growing follicles. [ 32 ] PCNA is a protein with a weight of 36,000 and it has been reported in fetal and adult ovaries of several mammals. [ 33 ] The expression of PCNA increased in the initiation of follicle growth, while there was no expression in granulosa cells of primordial follicles.…”