Dhakal Pramod, Tsunoda Nobuo, Nakai Rie, Nagaoka Kentaro, Nambo Yasuo, Sato Fumio, Taniyama Hiroyuki, Taya Kazuyoshi
Department of Basic Veterinary Science, United Graduate School of Veterinary Sciences, Gifu University, Gifu 501-1193, Japan ; Laboratory of Veterinary Physiology, Department of Veterinary Medicine, Faculty of Agriculture, Tokyo University of Agriculture and Technology, Tokyo 183-8509, Japan.
Shadai Corporation, Hokkaido 059-1432, Japan.
J Equine Sci. 2011;22(1):9-15. doi: 10.1294/jes.22.9. Epub 2011 Apr 26.
The aim of present study was to clarify the post-natal profile of follicle-stimulating hormone (FSH), luteinizing hormone (LH), immunoreactive (ir)-inhibin, progesterone, testosterone, and estradiol-17β, and their relationships in Thoroughbred colts. Six hundred and thirty-six colts were used for the study. Single plasma samples from each animal were harvested from the blood drawn through jugular venipuncture. The subjects were born with high amounts of progesterone, testosterone, and estradiol-17β, all of which dropped significantly and remained at lower levels till the end of 6 months. FSH decreased transiently after birth until day 12 and then gradually increased to peak at day 100 which then maintained in lesser levels towards the end of the studied period. LH was highest during birth which decreased until day 26 and then increased slowly to sub-birth levels up to day 90. Animals were born with high amounts of ir-inhibin. It dropped slowly and halved by day 20 and then decreased towards rest of the studied period. The increase in FSH is negatively correlated with the declining ir-inhibin levels. The early increase in FSH can be the indication of early post-natal maturation of the hypothalamic pituitary testicular axis that ultimately might be responsible for priming the testes for future development.
本研究的目的是阐明纯种马驹出生后促卵泡激素(FSH)、促黄体生成素(LH)、免疫反应性(ir)抑制素、孕酮、睾酮和雌二醇-17β的变化情况及其相互关系。本研究使用了636匹驹。从每只动物通过颈静脉穿刺采集的血液中获取单份血浆样本。这些动物出生时孕酮、睾酮和雌二醇-17β含量较高,所有这些激素在出生后均显著下降,并在6个月末一直维持在较低水平。FSH在出生后至第12天短暂下降,然后逐渐上升,在第100天达到峰值,随后在研究期末维持在较低水平。LH在出生时最高,在第26天前下降,然后缓慢上升,直至第90天达到出生前水平。动物出生时ir抑制素含量较高。它在第20天前缓慢下降,至第20天时减半,然后在研究期的剩余时间内持续下降。FSH的升高与ir抑制素水平的下降呈负相关。FSH的早期升高可能表明下丘脑-垂体-睾丸轴在出生后早期成熟,这最终可能是促使睾丸未来发育的原因。