RELEASE OF VASOACTIVE AGENTS FROM THE ISOLATED-PERFUSED HUMAN OVARY

Objective: To investigate local vascular control in the isolated perfu sed premenopausal human ovary by measuring flow-induced release of vas oactive substances. Design: Release of adenosine 5' triphosphate (ATP) , substance P (SP), endothelin (ET), and vasopressin (AVP) from the ov arian vascular endothelium was estimated in perfusate under basal cond itions and during two periods of increased flow. Main outcome measures : Vascular resistance; ATP, SP, ET and AVP release. Results: The mean ratio (pressure/flow during increased flow):(pressure/flow at basal fl ow) was 1.27 +/- 0.04 for the first, and 1.15 +/- 0.05 for the second period of increased flow (n = 10), indicating significant vasoconstric tion (P < 0.01 and 0.05, respectively), present to a greater extent du ring the first period of increased flow compared to the second (P < 0. 05). ATP release was seen in response to increased flow (n = 8, P < 0. 05). From 12 ovarian bed preparations, five released ET and SP and thr ee of these released AVP. Four of the five perfused ovaries that relea sed peptides contained either a developing follicle or a corpus luteum while all those that showed no peptide release were inactive. Conclus ions: ATP release may play a role in the local control of the human pr emenopausal ovarian vasculature independent of ovulatory status. Pepti des may also contribute to local vascular control in the ovary and the ir release from predominantly active ovaries suggests a relationship b etween ovulation and vascular endothelial function.