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

The study analyzes the expression of Follicle-stimulating hormone receptors (FSHR) in newborn and adult female horses to understand its role in ovarian function. The research shows that FSHR is present in horse ovaries from birth and its expression is consistent throughout different stages of the oestrous cycle.

Objectives and Methodology of the Study

• The main goal of this study was to inspect the presence and level of FSHR gene expression in the ovarian tissues of newborn and adult horses.
• Through techniques such as reverse transcription polymerase chain reaction, the expression of FSHR mRNA was observed.
• Other methods such as immunohistochemistry (IHC), immunofluorescence labelling (IF), and western blot were used to visualize the FSHR protein.

Findings of the Study

• Expression of the FSHR mRNA was detected in ovarian follicles, luteal tissue of adult mares, as well as in the ovaries of neonates. Notably, follicular growth of up to 4mm was already detected in the ovaries of newborn horses.
• The results showed that FSHR protein can also be found in granulosa cells, cumulus cells, and even inconsistently in the oocytes, regardless of the horse’s age or the stage of folliculogenesis. This implies that FSHR plays a significant role across various ovarian cells and developmental stages.
• The study found that FSHR expression in theca cells was lower compared to that in granulosa cells.
• Interestingly, FSHR was found to be abundant in the ovarian stroma cells of neonates but not adults. Furthermore, luteal cells tested positive for FSHR, independent of the stage of corpus luteum development.
• The researchers confirmed the presence of FSHR protein across various ovarian cell populations through western blotting.

Conclusion of the Study

• The research confirmed that FSHR is present in horse ovaries from birth and continues to express consistently throughout the oestrous cycle, thereby suggesting a constant role in ovarian function.