Physiology: Human follicular fluid maturity and endothelial cell mitogenesis

Follicular fluid, of varying maturity, (day 5–16 of cycle)was collected from the largest Graafian follicle of each of22 ovulatory patients during laparoscopic procedures. Threesamples were blood-stained and discarded. The mitogenic potentialof each sample was determined using bovine aortic endothelialcells in the CellTiter 96^TM Non-Radioactive Cell Proliferation/CytotoxicityAssay system. Intra- and inter-plate coefficients of variationwere <9%. The follicular fluid samples induced cell doublingtimes which varied from 12–24 h and final cell numberswhich, in the individual wells, ranged from 782–30 900(starting number 2000/well). Follicular fluid total proteincontent was unrelated to the mitogenic potential, (R² = 0%).Serum oestradiol was negatively correlated with the mitogenicpotential (R² = 26%). No correlation was found with day of themenstrual cycle (R² = 4.3%), maximum follicular diameter (R²= 1.8%), or serum concentration of progesterone (R² = 0.7%),luteinizing hormone (LH) (R² = 1.5%) or follicle stimulatinghormone (R² = 0.1%). Five subjects were in ‘early’and six in ‘mid’-follicular phase, six were in ‘early’and two in ‘late’ LH surge. There was no differencein the mitogenic response between these four groups by one-wayanalysis of variance (F = 0.21; P = 0.89). It is concluded thatthe mitogenic potential of human follicular fluid is not relatedto Graafian follicle maturity or, more particularly, to theLH surge.