title: Concentrations of bioactive and immunoactive luteinizing hormone in bovine anterior pituitary tissue.
abstract: Tissue concentrations of LH as determined by radioimmunoassay (RIA) may not accurately measure actual changes that could occur in biological activity of the hormone. To examine this possibility, pituitary homogenates from 135 beef cows in various physiological states were analyzed for content of LH by both RIA and an in vitro bioassay. The ratio of biological/immunological active concentrations of LH remained constant (.52 +/- .02) even though tissue concentrations of immunoactive LH differed among groups. Tissue concentrations of bioactive LH were linearly related to, and highly correlated with (P less than .001), tissue concentrations of immunoactive LH. These data indicate that only a fraction of the immunoactive LH in the bovine pituitary is biologically active. However, this fraction does not vary with the reproductive status or plane of nutrition.
authors.affiliation: Department of Animal Science, University of Wyoming, Laramie 82071.
authors.forename: G E
authors.initials: GE
authors.lastname: Moss
authors.forename: R P
authors.initials: RP
authors.lastname: Lemenager
authors.forename: J R
authors.initials: JR
authors.lastname: Parfet
authors.forename: B M
authors.initials: BM
authors.lastname: Adams
authors.forename: T E
authors.initials: TE
authors.lastname: Adams
mesh_terms: D000818:Animals; D001681:Biological Assay; D002417:Cattle / Q000502:physiology*; D005260:Female; D007986:Luteinizing Hormone / Q000032:analysis* / Q000276:immunology; D010903:Pituitary Gland, Anterior / Q000032:analysis*; D049590:Postpartum Period; D011247:Pregnancy; D011863:Radioimmunoassay
chemical_list: D007986:Luteinizing Hormone