Development and maintenance of a polycystic condition in ovaries autotransplanted under the kidney capsule

Abstract

A single injection of estradiol valerate (EV) produces a polycystic ovarian (PCO) condition in the rat. The development of the PCO condition coincides with alterations in the endogenous plasma gonadotropin patterns, suggesting that PCO may be a response to abnormal gonadotropin stimulation. Other factors, however, such as direct autonomic innervation, also contribute significantly to the regulation of the ovary and could be important in generating and/or maintaining PCO. We have, therefore, removed and autotransplanted one ovary in each of eight rats under the capsule of the ipsilateral kidney, thus totally disrupting its innervation. The animals were injected with EV and both ovaries of each animal were examined 8 weeks later. In a second group of animals, we induced the PCO condition, autotransplanted one polycystic ovary in each animal under the kidney capsule, and examined the ovaries 2 weeks later. In both groups the autotransplanted ovaries exhibited the full range of polycystic morphology, as did the intact ovary in each animal. We conclude that since a major perturbation in innervation affects neither the development nor the maintenance of PCO, autonomic innervation does not play a crucial role in this disorder.

Thecal and interstitial cells in polycystic ovaries (PCO) in the rat

“…Recent evidence from our laboratory (unpublished) suggests that the macrocyst is the end product of atresia of type I11 large follicular structures Desjardins and Brawer, 1989). This is consistent with evidence from other models of PCO showing disturbances in steroidogenic activity in large, normalappearing antral follicles (Zoller and Axelson, 1986).…”

“…Thecal cell profiles were identified and localized to healthy secondary follicles, atretic secondary follicles, precystic follicles, or cystic follicles. A light microscopic slide containing the same section as the electron microscopic grid was studied to identify the follicular structure under examination according to previously established criteria Desjardins and Brawer, 1989).…”

Remission of the polycystic ovarian condition (PCO) in the rat following hemiovariectomy

“…These are comprised of a membrana granulosa and thecal cell layers similar to those characterizing Graafian follicles. The type I11 large follicular structure, however, differs from a Graafian follicle in that it is often larger, exhibits mitotic figures in the perimural granulosa cells Desjardins and Brawer, 1989), and, as demonstrated by the present study, contains no ovum. Paradoxically, it is the only follicular structure in the polycystic ovary in which granulosa cells bind LH (hCG) , and it is, therefore, the only structure that could be readily luteinized following a n LH surge.…”

“…The loss of a n ovulatory LH surge accounts for the lack of corpora lutea, and the atresia of secondary follicles results in the numerous clusters of hypertrophied lipid-containing secondary interstitial cells. The cysts themselves represent partial or arrested atresia of large secondary follicles or type I11 large follicular structures Desjardins and Brawer, 1989). The processes of follicular recruitment and atresia that produce the polycystic ovary seems to be driven by a specific plasma gonadotropin pattern (McCarthy et al, 1986Grosser et al, 1987).…”

The New Zealand obese mouse model of obesity insulin resistance and poor breeding performance: evaluation of ovarian structure and function

“…Cells facing the cyst were flat and epithelioid, and the cyst fluid invariably contained macrophages (Manneras et al 2007). Type III follicles were defined as large follicular structures (Brawer et al 1986, Desjardins & Brawer 1989) and distinguished from large secondary follicles by virtue of the fact that they did not contain ova. The granulosa membrane was thick and often plicate.…”