title: Effects of colostrum versus formula feeding on hepatic glucocorticoid and α₁- and β₂-adrenergic receptors in neonatal calves and their effect on glucose and lipid metabolism.
abstract: Neonatal energy metabolism in calves has to adapt to extrauterine life and depends on colostrum feeding. The adrenergic and glucocorticoid systems are involved in postnatal maturation of pathways related to energy metabolism and calves show elevated plasma concentrations of cortisol and catecholamines during perinatal life. We tested the hypothesis that hepatic glucocorticoid receptors (GR) and α₁- and β₂-adrenergic receptors (AR) in neonatal calves are involved in adaptation of postnatal energy metabolism and that respective binding capacities depend on colostrum feeding. Calves were fed colostrum (CF; n=7) or a milk-based formula (FF; n=7) with similar nutrient content up to d 4 of life. Blood samples were taken daily before feeding and 2h after feeding on d 4 of life to measure metabolites and hormones related to energy metabolism in blood plasma. Liver tissue was obtained 2 h after feeding on d 4 to measure hepatic fat content and binding capacity of AR and GR. Maximal binding capacity and binding affinity were calculated by saturation binding assays using [(3)H]-prazosin and [(3)H]-CGP-12177 for determination of α₁- and β₂-AR and [(3)H]-dexamethasone for determination of GR in liver. Additional liver samples were taken to measure mRNA abundance of AR and GR, and of key enzymes related to hepatic glucose and lipid metabolism. Plasma concentrations of albumin, triacylglycerides, insulin-like growth factor I, leptin, and thyroid hormones changed until d 4 and all these variables except leptin and thyroid hormones responded to feed intake on d 4. Diet effects were determined for albumin, insulin-like growth factor I, leptin, and thyroid hormones. Binding capacity for GR was greater and for α₁-AR tended to be greater in CF than in FF calves. Binding affinities were in the same range for each receptor type. Gene expression of α₁-AR (ADRA1) tended to be lower in CF than FF calves. Binding capacity of GR was related to parameters of glucose and lipid metabolism, whereas β₂-AR binding capacity was negatively associated with glucose metabolism. In conclusion, our results indicate a dependence of GR and α₁-AR on milk feeding immediately after birth and point to an involvement of hepatic GR and AR in postnatal adaptation of glucose and lipid metabolism in calves.
authors.affiliation: Institute of Nutritional Physiology "Oskar Kellner,", Leibniz Institute for Farm Animal Biology (FBN), 18196 Dummerstorf, Germany.
authors.forename: C T
authors.initials: CT
authors.lastname: Schäff
authors.affiliation: Institute of Nutritional Physiology "Oskar Kellner,", Leibniz Institute for Farm Animal Biology (FBN), 18196 Dummerstorf, Germany.
authors.forename: D
authors.initials: D
authors.lastname: Rohrbeck
authors.affiliation: Institute of Nutritional Physiology "Oskar Kellner,", Leibniz Institute for Farm Animal Biology (FBN), 18196 Dummerstorf, Germany.
authors.forename: J
authors.initials: J
authors.lastname: Steinhoff-Wagner
authors.affiliation: Institute of Behavioural Physiology, Leibniz Institute for Farm Animal Biology (FBN), 18196 Dummerstorf, Germany.
authors.forename: E
authors.initials: E
authors.lastname: Kanitz
authors.affiliation: Institute of Animal Science, Physiology and Hygiene Unit, University of Bonn, 53115 Bonn, Germany.
authors.forename: H
authors.initials: H
authors.lastname: Sauerwein
authors.affiliation: Veterinary Physiology, Vetsuisse Faculty, University of Bern, 3001 Bern, Switzerland.
authors.forename: R M
authors.initials: RM
authors.lastname: Bruckmaier
authors.affiliation: Institute of Nutritional Physiology "Oskar Kellner,", Leibniz Institute for Farm Animal Biology (FBN), 18196 Dummerstorf, Germany. Electronic address: hammon@fbn-dummerstorf.de.
authors.forename: H M
authors.initials: HM
authors.lastname: Hammon
mesh_terms: D000818:Animals; D000831:Animals, Newborn / Q000378:metabolism*; D002417:Cattle / Q000378:metabolism*; D003126:Colostrum / Q000378:metabolism*; D003907:Dexamethasone / Q000378:metabolism; D004032:Diet / Q000662:veterinary; D005223:Fats / Q000378:metabolism; D005260:Female; D005938:Glucocorticoids / Q000378:metabolism; D005947:Glucose / Q000378:metabolism; D006003:Glycogen / Q000378:metabolism; D006728:Hormones / Q000097:blood; D006854:Hydrocortisone / Q000097:blood; D050356:Lipid Metabolism; D008099:Liver / Q000378:metabolism; D008297:Male; D008892:Milk / Q000378:metabolism*; D011247:Pregnancy; D011412:Propanolamines / Q000032:analysis; D012333:RNA, Messenger / Q000378:metabolism; D011897:Random Allocation; D011941:Receptors, Adrenergic / Q000378:metabolism*; D011965:Receptors, Glucocorticoid / Q000378:metabolism*
chemical_list: D005223:Fats; D005938:Glucocorticoids; D006728:Hormones; D011412:Propanolamines; D012333:RNA, Messenger; D011941:Receptors, Adrenergic; D011965:Receptors, Glucocorticoid; D003907:Dexamethasone; D006003:Glycogen; D005947:Glucose; C033394:CGP 12177; D006854:Hydrocortisone
keywords: adrenergic receptor; calf; energy metabolism; glucocorticoid receptor; milk diet