Lee S M, Hutson J M
F. Douglas Stephens Surgical Research Laboratory, Royal Children's Hospital, Melbourne, Australia.
Anat Rec. 1999 Jul 1;255(3):306-15. doi: 10.1002/(SICI)1097-0185(19990701)255:3<306::AID-AR6>3.0.CO;2-B.
Androgens have been postulated to have a major role in testicular descent via regression of the cranial suspensory ligament, which in normal rodents anchors the ovary to the retroperitoneum near the lower pole of the kidney. This study aimed to quantitate the degree of descent of the foetal ovary in androgen-treated female mice to determine the role of androgens in regression of the cranial suspensory ligament and descent of the testis. Time-pregnant mice were injected with testosterone propionate or methyl testosterone (2.5-3.0 mg) in vehicle on day 13 or 14. Control animals received vehicle only. Newborn mice were anaesthetised and dissected for macroscopic anatomy of the ovary, which was quantified by measuring the vertical distance from the lower pole of the kidney to the lower pole of the ovary. Histological analysis was also performed. The external genitalia were masculinised in all females exposed to prenatal androgens. The ovaries of treated animals were mobile, with no cranial suspensory ligament, and located slightly caudal to the kidney. Wolffian duct structures were identifiable, but the gubernaculum was qualitatively unchanged compared with control females. The ovary was displaced caudally (P< 0.001), but only 15-25% of the distance to the lower abdomen. Exogenous androgens induce regression of the cranial suspensory ligament, causing the ovary to be more mobile and lower in the abdominal cavity. However, since the testicular position at birth is at or below the bladder neck, androgen-mediated regression of the cranial suspensory ligament is only an adjunct to the control of transabdominal testicular descent.
雄激素被认为通过颅悬韧带的退化在睾丸下降过程中起主要作用，在正常啮齿动物中，该韧带将卵巢固定于肾下极附近的腹膜后。本研究旨在量化雄激素处理的雌性小鼠中胎儿卵巢的下降程度，以确定雄激素在颅悬韧带退化和睾丸下降中的作用。孕鼠在第13或14天经载体注射丙酸睾酮或甲基睾酮（2.5 - 3.0mg）。对照动物仅接受载体。新生小鼠麻醉后解剖以进行卵巢大体解剖，通过测量从肾下极到卵巢下极的垂直距离进行量化。还进行了组织学分析。所有暴露于产前雄激素的雌性小鼠外生殖器均出现雄性化。处理组动物的卵巢可活动，无颅悬韧带，位于肾尾侧稍远处。可识别出中肾管结构，但与对照雌性相比，引带在质量上无变化。卵巢向尾侧移位（P < 0.001），但仅为到下腹部距离的15 - 25%。外源性雄激素诱导颅悬韧带退化，使卵巢在腹腔内更易活动且位置更低。然而，由于出生时睾丸位置在膀胱颈或其下方，雄激素介导的颅悬韧带退化只是经腹睾丸下降控制的一个辅助因素。
