Acute regulation of plasma insulin-like peptide 3 concentrations by luteinizing hormone in male goats

• Published in: Theriogenology 2016-08, Vol.86 (3), p.749-756
• Main Authors: Hannan, M.A., Kawate, N., Fukami, Y., Pathirana, I.N., Büllesbach, E.E., Inaba, T., Tamada, H.
• Format: Article
• Language: English
• Subjects: Animals; Chorionic Gonadotropin - pharmacology; Gene Expression Regulation - physiology; GnRH; Goats - blood; Goats - physiology; Gonadotropin-Releasing Hormone - analogs & derivatives; Gonadotropin-Releasing Hormone - pharmacology; hCG; INSL3; Insulin - genetics; Insulin - metabolism; Luteinizing Hormone - pharmacology; Male; Male goat; Proteins - genetics; Proteins - metabolism; Testosterone; Testosterone - blood
• ISSN: 0093-691X; 1879-3231
• DOI: 10.1016/j.theriogenology.2016.02.028

Recently, it was reported that in bulls secretion of insulin-like peptide 3 (INSL3) in blood occurred in a pulsatile manner and was acutely regulated by LH. In the present study, the acute regulation of plasma INSL3 and its temporal relationships with LH and testosterone were examined in six sexually matured male goats using the following experimental design. (1) After stimulating LH release by administering a GnRH analogue, blood levels of LH, INSL3, and testosterone were monitored at 15-minute intervals for 2 hours followed by hourly intervals up to 8 hours. (2) After activation of the LH receptor by hCG blood levels of INSL3 and testosterone were determine at 15-minute intervals for 2 hours, followed by hourly intervals up to 8 hours, daily intervals up to Day 8, and finally on Day 12. (3) The release of LH, INSL3, and testosterone in normal physiology was established at 15-minute intervals for an 8-hour session. Concentrations of LH, INSL3, and testosterone in plasma were measured by enzyme-immunoassays. After GnRH treatment, mean plasma concentrations of all three hormones increased (P