[Association between renin activity, angiotensin II and ovarian hyperstimulation syndrome]

To investigate the association between renin-like activity (RA) and angiotensin II (A II) and the ovarian hyperstimulation syndrome (OHSS).

Blood samples were taken from 42 patients undergoing in vitro fertilization (IVF). According to the ovarian stimulating response, the patients were divided into 4 groups: group I, low responders, 7 cases; group II, moderate responders, 8 cases; group III a high responders without using albumin, 7 cases, group III b, high responders with albumin, 10 cases; group IV, severe and moderate OHSS, 10 cases. 5 patients for intrauterin insemination with natural cycle as control. Follicular fluid (FF) was collected at oocyte retrieval from 28 IVF patients (including 7 OHSS patients). Fluid from ascites and hydrothorax was obtained from 3 OHSS patients, and peritoneal fluid obtained from 5 infertility patients by laparoscopy and ascitic fluid obtained from 6 ovarian carcinoma patients served as control. RA and A II levels were measured by radioimmunoassay.

Plasma RA and A II levels at mid-luteal phase from OHSS patients [(19.9 +/- 19.0) micrograms.L-1.h-1 and (397.0 +/- 378.2) ng/L] were significantly higher than those from the other patients (P < 0.01-0.05), also the levels at mid-luteal phase from IVF patients were significantly higher than those at late-follicular phase [(4.1 +/- 2.9)-(4.9 +/- 3.2) micrograms.L-1.h-1 Vs (1.5 +/- 0.9)-(1.9 +/- 1.0) micrograms.L-1.h-1, (85.5 +/- 49.5)-(109.4 +/- 46.0) ng/L Vs (33.6 +/- 15.9)-(37.0 +/- 17.1) ng/L, P < 0.01-0.05]. RA and A II levels in FF were significant higher than those in plasma (P < 0.01-0.05). A II in ascitic fluid in OHSS patients was 4 to 8 times higher than that in plasma, while RA in ascitic fluid was 1.5 to 3 times higher than that in plasma, but the levels of A II and RA in controls were very low. The plasma RA and A II levels dropped very significantly along with clinical improvement (P < 0.01).

These findings suggest that RA and A II are associated with the pathogenesis of capillary leakage in OHSS.