Ghrelin is a 28-amino acid peptide hormone that regulates ovarian steroid hormone synthesis; however, there is limited evidence regarding the regulation of this pathway by ghrelin in mice ovary. Thus, we aimed to investigate whether central ghrelin action plays a role in murine reproductive health by inhibiting steroid synthesis. Further, we sought to examine the mechanism of central ghrelin action in ovarian steroid hormone synthesis. After the administration of intracerebroventricular ghrelin (1 nmol), we found reduced serum concentrations of oestradiol and progesterone and reduced secretion of follicle-stimulating hormone and luteinising hormone. Although ghrelin reduced 3β-hydroxysteroid dehydrogenase mRNA and protein levels in the hypothalamus, it did not affect the expression of steroidogenic acute regulatory protein and cytochrome P450 17A1. In the ovary, central ghrelin regulation indirectly inhibited the mRNA and protein levels of steroidogenic acute regulatory protein, cytochrome P450 17A1, and 3β-hydroxysteroid dehydrogenase. Moreover, no changes were observed in the expression of proliferating cell nuclear antigen and phosphorylation of extracellular signal-regulated kinase. We hypothesised that central ghrelin regulation suppressed serum oestradiol and progesterone levels by indirectly inhibiting the expression of steroidogenic acute regulatory protein, cytochrome P450 17A1, and 3β-hydroxysteroid dehydrogenase in the ovary. In this regulation, the suppressed secretion of the follicle-stimulating hormone and luteinising hormone in the pituitary by ghrelin could be involved. Furthermore, hypothalamic 3β-hydroxysteroid dehydrogenase expression is reduced by ghrelin injection.

Ghrelin是一种28个氨基酸的肽激素，可调节卵巢类固醇激素的合成。然而，关于生长素释放肽在小鼠卵巢中对该途径的调控作用的证据有限。因此，我们旨在研究中性生长激素释放肽的作用是否通过抑制类固醇合成在鼠的生殖健康中发挥作用。此外，我们试图检查在卵巢甾体激素合成中中心生长素释放肽作用的机制。施用脑室内生长素释放肽（1 nmol）后，我们发现血清雌二醇和孕酮的浓度降低，刺激卵泡的激素和黄体生成素的分泌减少。尽管ghrelin降低了下丘脑中的3β-羟类固醇脱氢酶mRNA和蛋白水平，但它并未影响类固醇生成的急性调节蛋白和细胞色素P450 17A1的表达。在卵巢中，ghrelin中心调节间接抑制类固醇生成的急性调节蛋白，细胞色素P450 17A1和3β-羟基类固醇脱氢酶的mRNA和蛋白水平。此外，未观察到增殖细胞核抗原的表达和细胞外信号调节激酶的磷酸化的变化。我们假设中央生长素释放肽调节通过间接抑制卵巢中类固醇生成的急性调节蛋白，细胞色素P450 17A1和3β-羟基类固醇脱氢酶的表达而抑制血清雌二醇和孕酮水平。在该法规中，可能涉及生长素释放肽抑制垂体中促卵泡激素和黄体生成激素的分泌。此外，通过ghrelin注射降低了下丘脑3β-羟基类固醇脱氢酶的表达。