Fatty acids are precursor of paracrine hormones involved in dominance, ovulation and atresia mechanisms. Active and non-active follicles of Friesian dairy cows were studied in order to investigate their fatty acids profiles. Estrogen activity of follicles was defined as the ratio of estrogens to progesterone concentrations in follicular fluid. Follicles were assigned as active if their ratio was higher than one. Follicular fluid lipids of 11 active and 11 non-active follicles were extracted using the Bligh & Dyer method, methylated and separated using gas chromatography. Concentrations were expressed as the percentage of total lipids (mean ± SEM, n = 11). Active follicles showed lower oleic (11.3% ± 0.63 vs 14.0% ± 0.93, p < 0.05), arachidonic (3.0% ± 0.31 vs 4.2% ± 0.36, p < 0.05) and higher linoleic (55.1% ± 1.05 vs 51.1% ± 1.02, p < 0.05) acid concentrations. These variations in fatty acid concentrations are interesting in understanding fatty acid metabolism during folliculogenesis. Decrease in arachidonic acid concentrations might be due to increased membrane incorporation as active follicles are not going in atresia and as such need improved membrane synthesis to sustain follicular growth. Arachidonic acid as a precursor of prostaglandin may also play a role in the hormonal paracrine regulation of the ovulatory and angiogenesis processes.
Effect of Follicle Oestrogen Activity on Fatty Acids Profile in Bovine Follicular Fluid
RENAVILLE, Benedicte France Ghislaine;COMIN, Antonella;FAZZINI, Uberto;PRANDI, Alberto
2006-01-01
Abstract
Fatty acids are precursor of paracrine hormones involved in dominance, ovulation and atresia mechanisms. Active and non-active follicles of Friesian dairy cows were studied in order to investigate their fatty acids profiles. Estrogen activity of follicles was defined as the ratio of estrogens to progesterone concentrations in follicular fluid. Follicles were assigned as active if their ratio was higher than one. Follicular fluid lipids of 11 active and 11 non-active follicles were extracted using the Bligh & Dyer method, methylated and separated using gas chromatography. Concentrations were expressed as the percentage of total lipids (mean ± SEM, n = 11). Active follicles showed lower oleic (11.3% ± 0.63 vs 14.0% ± 0.93, p < 0.05), arachidonic (3.0% ± 0.31 vs 4.2% ± 0.36, p < 0.05) and higher linoleic (55.1% ± 1.05 vs 51.1% ± 1.02, p < 0.05) acid concentrations. These variations in fatty acid concentrations are interesting in understanding fatty acid metabolism during folliculogenesis. Decrease in arachidonic acid concentrations might be due to increased membrane incorporation as active follicles are not going in atresia and as such need improved membrane synthesis to sustain follicular growth. Arachidonic acid as a precursor of prostaglandin may also play a role in the hormonal paracrine regulation of the ovulatory and angiogenesis processes.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
