A new in vivo microvascular preparation of the hamster ovary

Ovarian function in the cycling female is intimately related to and dependent upon significant microvascular regulation and restructuring. To enable investigation of the microvascular determinants of ovarian function, we present an in vivo preparation of the golden hamster ovary. The preparation does not compromise the ovarian vascular supply. The viability and responsiveness of the preparation were confirmed by quantifying arteriolar responses to vasoactive agents in 17 hamsters. Small surface arterioles (mean diameter 15-16 microns) responded with statistically significant changes in diameter to adenosine and oxygen and showed significant, dose-dependent constriction in response to norepinephrine and the NO synthase inhibitor L-NAME. Other key findings included extremely high microvascular permeability that varied with the day of the estrous cycle and functionally significant architectural features of the utero-ovarian vascular network. Potential applications of the preparation include elucidation of the role of the microvasculature in follicular development and luteal regression, investigation of utero-ovarian crossregulation, and development of a model for the study of ovarian angiogenesis and vascular regression.