Abstract
BACKGROUND: Successful reproduction relies on a functioning hypothalamic-pituitary-gonad axis. Damage to this axis disrupts the estrus cycle and reproductive capability. OBJECTIVE: This study aimed to evaluate the effects of single or multiple platelet-rich plasma (PRP) injections on repairing the damaged hypothalamic arcuate nucleus (ARC) and restoring the estrus cycle in Wistar rats. MATERIALS AND METHODS: 90 female Wistar rats (2-3 months old, 250-280 gr) with regular estrous cycles were divided into a control group and 8 experimental groups (n = 10/each). After bilateral stereotaxic chemical surgery of the ARC using quinolinic acid (500 nmol/2 μ l), the experimental rats were categorized into several treatment regimens: ARC - (no treatment), 1 PRP injection (immediately, 24 hr, 48 hr, and 72 hr postsurgery), 2 PRP injections (immediately, 24 hr), 3 PRP injections (immediately, 24 hr, and 48 hr), and 4 PRP injections (immediately, 24 hr, 48 hr, and 72 hr). Vaginal smear cytology was performed daily for 2.5 months. In the end, rats brains were removed and divided for real-time polymerase chain reaction analysis of kisspeptin, neurokinin B, and dynorphin, as well as for ARC cell counting. RESULTS: Vaginal smear cytology indicated that PRP administration gradually restored the estrous cycle. Compared to the ARC - group, PRP treatment significantly increased ARC cell density (p = 0.012) and mRNA levels of kisspeptin, neurokinin B, and dynorphin (p < 0.001). CONCLUSION: These findings not only emphasized the importance of the ARC for the regularity of estrous cycle but also showed the potential effects of local PRP treatment in contribution to the protection/reconstruction of ARC.