The role of interferon-tau (IFNT) in luteal gene expression, steroidogenesis, and luteal lifespan in the ewe
Date
2009
Authors
Bott, Rebecca Clark, author
Bruemmer, Jason, advisor
Niswender, Gordon, advisor
Journal Title
Journal ISSN
Volume Title
Abstract
Interferon-tau (IFNT) was evaluated for endocrine actions on the corpus luteum (CL). The hypothesis was that infusion of IFNT would increase luteal expression of interferon-stimulated gene (ISG)-15, and the length of time for ewes to return to estrus. Osmotic pumps containing 200 μg IFNT or BSA (n=12 each) were connected to the uterine vein of non-pregnant ewes 10 days post-estrus. Messenger RNA encoding ISG15 was elevated in CL from pregnant and IFNT-infused ewes (P<0.05) compared to nonpregnant and BSA-treated ewes, respectively. Luteal mRNA encoding ISG15 from ewes treated with IFNT was greater than in ewes treated with BSA (P<0.05). Serum concentrations of progesterone were not different in ewes that received infusions of BSA or IFNT. Progesterone decreased by six hours (P<0.05) in ewes that received BSA+PGF or IFNT+PGF, but did not differ in ewes that received infusions of IFNT +/- PGF at 8, 10, or 12 hours after PGF. There were no differences in prostaglandin E synthase (PGES) or prostaglandin F synthase (PGFS), or in prostaglandin dehydrogenase (PGDH), steroidogenic acute regulatory protein (StAR), peripheral type benzodiazepine receptor (PBR), cytochrome P450 side chain cleavage enzyme (CYP-11A), or 3μ-hydroxysteroid dehydrogenase (3μ-HSD). Seven day infusion of IFNT during the time frame of maternal recognition of pregnancy resulted in 20% of IFNT-treated ewes returning to estrus by d19 compared to 100% of BSA-treated ewes (P<0.01). In conclusion IFNT acts systemically, alters gene expression in the corpus luteum, and decreases the number of ewes returning to estrus by d19.
Description
Rights Access
Subject
corpus luteum
ISG-15
interferon-tau
interferons
ovine
progesterone
physiology