| Popis: |
To assess the relationship (s) among concentrations of insulin-like growth factor-I (IGF-I) in blood plasma and ovarian follicular fluid (FFL), and concentrations of steroids in FFL of individual preovulatory equine follicles, FFL and blood plasma were collected simultaneously from mares between Days 1 and 6 of oestrus. Follicles were placed into two groups: early oestrus (EE) (Day 1 or 2 of oestrus, n = 12) and late oestrus (LE) (Day 3–6 of oestrus, n = 10). LE follicles were larger and had greater (P 0.10) to any steroid in FFL. However, the ratio of FFL: plasma IGF-I was correlated with FFL oestradiol (r = 0.75,P < 0.001) and FFL androstenedione (r = 0.43, P < 0.05). These results support the hypothesis that changing permeability of follicles to plasma IGF-I may allow for increased IGF-I levels in follicles which, in turn, may enhance follicular differentiation. |
