title: Diurnal variations in the concentration, arteriovenous difference, extraction ratio, and uptake of 3-hydroxybutyrate and plasma free fatty acids in the hind limb of lactating sheep.
abstract: Four lactating sheep were used to study diurnal variations in the concentration, arteriovenous concentration difference, extraction ratio, and uptake of 3-hydroxybutyrate and plasma free fatty acids by the hind limb of the lactating sheep. The arterial and venous concentrations of 3-hydroxybutyrate showed significant diurnal variations, which appear to be related to the feeding regimen, since values declined after feed withdrawal and rose after refeeding. Throughout the experimental period uptake of 3-hydroxybutyrate by the hind-limb was consistent and none of the small variations in arteriovenous difference, extraction ratio, or uptake of 3-hydroxybutyrate by the hind limb was statistically significant. By contrast, free fatty acid concentrations in arterial blood rose steadily after feed withdrawal. Except at feeding time, there was an output of free fatty acid by the hind limb.
authors.affiliation: Department of Agricultural Biochemistry and Nutrition, University of Newcastle upon Tyne, United Kingdom.
authors.forename: A I
authors.initials: AI
authors.lastname: Osuagwuh
authors.forename: J
authors.initials: J
authors.lastname: Metcalfe
authors.forename: T E
authors.initials: TE
authors.lastname: Weekes
authors.forename: R R
authors.initials: RR
authors.lastname: Smithard
mesh_terms: D020155:3-Hydroxybutyric Acid; D000818:Animals; D002339:Carotid Arteries; D002940:Circadian Rhythm; D005230:Fatty Acids, Nonesterified / Q000097:blood*; D005260:Female; D005268:Femoral Vein; D006885:Hydroxybutyrates / Q000097:blood / Q000378:metabolism*; D007774:Lactation / Q000097:blood / Q000378:metabolism*; D011247:Pregnancy; D012756:Sheep / Q000378:metabolism*
chemical_list: D005230:Fatty Acids, Nonesterified; D006885:Hydroxybutyrates; D020155:3-Hydroxybutyric Acid