Inhibin/activin beta-subunit monomer: isolation and characterization.

Using an activin RIA that showed limited cross-reaction with inhibin, activin immunoactivity was monitored throughout the isolation of activin from bovine follicular fluid and side-fractions during the isolation of human recombinant inhibin. Two peaks of activin immunoactivity were identified in both materials and isolated to homogeneity by dye affinity chromatography, hydrophobic interaction and gel permeation chromatography, and reverse phase HPLC. The purified proteins in all four peaks had terminal amino acid sequences identical to those of the inhibin/activin beta-subunit.

Serum FSH-suppressing activity of human recombinant inhibin A in male and female rats.

After a single i.v. injection of purified human recombinant inhibin A (hr-inhibin) or bovine follicular fluid (bFF) to 3-day castrated 35-day-old male rats, serum FSH concentrations fell (P less than 0.

Differences in gonadotrophin-stimulated cyclic AMP production by granulosa cells from booroola x merino ewes which were homozygous, heterozygous or non-carriers of a fecundity gene influencing their ovulation rate.

Granulosa cells from follicles of different sizes from Booroola x Merino ewes which were homozygous (FF), heterozygous (F+) or non-carriers(++) of a fecundity gene were obtained 0-48 h after cloprostenol injection on Day 10 of the oestrous cycle. The highest mean amounts of cAMP produced by the cells did not differ between the genotypes. However, in the ++ ewes it was attained by cells from follicles greater than or equal to 5 mm in diameter, whereas in F+ and FF ewes it was attained by cells from follicles 3-4.

Influence of follicular health on the steroidogenic and morphological characteristics of bovine granulosa cells in vitro.

In 24-h cultures, steroid production by cells from non-atretic follicles increased with increasing follicular diameter. Cells from atretic follicles, of all sizes, produced low amounts of oestradiol-17 beta, but very high amounts of progesterone, relative to cells from non-atretic follicles. Increasing the culture period to 72 h caused little change in daily progesterone and oestradiol-17 beta production by granulosa cells from atretic follicles.

Use of bovine follicular fluid to increase ovulation rate or prevent ovulation in sheep.

Romney ewes were injected intramuscularly once or twice daily for 3 days with 0, 0.1, 0.5, 1 or 5 ml of bovine follicular fluid (bFF) treated with dextran-coated charcoal, starting immediately after injection of cloprostenol to initiate luteolysis on Day 10 of the oestrous cycle.