Messini Christina I, Anifandis George, Georgoulias Panagiotis, Dafopoulos Konstantinos, Sveronis George, Daponte Alexandros, Messinis Ioannis E
Department of Obstetrics and Gynaecology, Faculty of Medicine, School of Health Sciences, University of Thessaly, 41500 Larissa, Greece.
Department of Nuclear Medicine, Faculty of Medicine, School of Health Sciences, University of Thessaly, 41500 Larissa, Greece.
Medicina (Kaunas). 2024 Dec 11;60(12):2039. doi: 10.3390/medicina60122039.
A similar secretory pattern of prolactin (PRL) and growth hormone (GH) during the menstrual cycle has been reported in response to a high dose of ghrelin in adult healthy women. The present study aimed to assess the pattern of PRL and GH secretions in response to a submaximal dose of ghrelin during different menstrual phases in adult healthy women. Eight female subjects with normal cyclicity were enrolled. These subjects were either in the early follicular (EF), late follicular (LF), or mid-luteal (ML) phase of their cycles. Each subject received an IV dose of normal saline (2 mL each time) during the first cycle after enrollment, followed by an IV dose of ghrelin (0.30 μg/kg bw) in the second cycle. The blood samples were collected before and after the IV dosage at -15, 0, 15, 30, 45, 60, 75, 90 and 120 min, where 0 min denotes the time of IV dosage. All the enrolled subjects experienced ovulatory cycles as assessed by increased serum progesterone levels. Serum estradiol levels were significantly higher in the LF than in the EF ( < 0.001) and ML phases ( < 0.01); these levels were also significantly higher in the ML than in the EF phase ( < 0.01). The administration of saline did not affect serum GH or PRL levels. Following the administration of ghrelin, plasma ghrelin levels and serum GH levels increased significantly ( < 0.001). The response amplitude of GH was similar in the three stages of cycle 2. In contrast to GH, the ghrelin injection induced a significant increase in serum PRL levels only in the LF phase ( < 0.05). These results show, for the first time, a different pattern of PRL and GH in response to a submaximal dose of ghrelin during the normal menstrual cycle. It is suggested that the ghrelin threshold for pituitary lactotrophs is higher than for somatotrophs and that, unlike GH, ghrelin-stimulated PRL secretion can be influenced by ovarian steroids.
据报道，成年健康女性在月经周期中，高剂量胃饥饿素会引发类似的催乳素（PRL）和生长激素（GH）分泌模式。本研究旨在评估成年健康女性在不同月经周期阶段，次最大剂量胃饥饿素刺激下PRL和GH的分泌模式。招募了8名月经周期正常的女性受试者。这些受试者处于月经周期的卵泡早期（EF）、卵泡晚期（LF）或黄体中期（ML）。每位受试者在入组后的第一个周期接受静脉注射生理盐水（每次2 mL），在第二个周期接受静脉注射胃饥饿素（0.30 μg/kg体重）。在静脉注射前及注射后-15、0、15、30、45、60、75、90和120分钟采集血样，其中0分钟表示静脉注射时间。通过血清孕酮水平升高评估，所有入组受试者均经历排卵周期。血清雌二醇水平在LF期显著高于EF期（<0.001）和ML期（<0.01）；在ML期也显著高于EF期（<0.01）。注射生理盐水不影响血清GH或PRL水平。注射胃饥饿素后，血浆胃饥饿素水平和血清GH水平显著升高（<0.001）。周期2的三个阶段中GH的反应幅度相似。与GH不同，注射胃饥饿素仅在LF期引起血清PRL水平显著升高（<0.05）。这些结果首次表明，在正常月经周期中，次最大剂量胃饥饿素刺激下PRL和GH呈现不同模式。提示垂体催乳细胞对胃饥饿素的阈值高于生长激素细胞，且与GH不同；胃饥饿素刺激的PRL分泌会受卵巢类固醇影响。
