Role of catecholamines in glucagon-induced thermogenesis.
The present work was undertaken in order to investigate whether the observed thermogenesis following glucagon injection requires the participation of catecholamines. Our experiments aim at studying the effects of intraperitoneal injection of glucagon on metabolic rates, plasma catecholamine and fuel metabolites in guanethidine-treated ducklings reared at thermoneutrality (25 degrees C). The chronic guanethidine treatment induced a marked decrease in catecholamines levels in peripheral tissues (heart, muscle and intestine) but not in adrenals. At thermoneutrality, intraperitoneal injection of glucagon had lower thermogenic effects in guanethidine-treated compared to control ducklings. Glucagon injection elicited a concomitant increase of plasma norepinephrine, metabolic rate and energy metabolites in control ducklings, whereas in guanethidine-treated ducklings, the plasma catecholamines and metabolic rate did not undergo any consistent change. The thermogenic action of glucagon in birds involves at least the mobilization of lipids and catecholaminergic system stimulation.
Laboratoire de Physiologie des Régulations Energétiques, Cellulaires et Moléculaires UMR 5123 CNRS, Villeurbanne, France.
Y
Y
Filali-Zegzouti
H
H
Abdelmelek
J L
JL
Rouanet
J M
JM
Cottet-Emard
J M
JM
Pequignot
H
H
Barré
D000273:Adipose Tissue / Q000187:drug effects / Q000378:metabolism*; D018663:Adrenergic Agents / Q000494:pharmacology; D000818:Animals; D001786:Blood Glucose / Q000187:drug effects / Q000378:metabolism; D002395:Catecholamines / Q000378:metabolism*; D015536:Down-Regulation / Q000187:drug effects / Q000502:physiology; D004372:Ducks; D004734:Energy Metabolism / Q000187:drug effects / Q000502:physiology*; D005230:Fatty Acids, Nonesterified / Q000097:blood; D005934:Glucagon / Q000378:metabolism* / Q000494:pharmacology; D006145:Guanethidine / Q000494:pharmacology; D007274:Injections, Intraperitoneal; D008297:Male; D009638:Norepinephrine / Q000097:blood / Q000378:metabolism; D013564:Sympathetic Nervous System / Q000187:drug effects / Q000378:metabolism*; D022722:Thermogenesis / Q000187:drug effects / Q000502:physiology*; D015854:Up-Regulation / Q000187:drug effects / Q000502:physiology
D018663:Adrenergic Agents; D001786:Blood Glucose; D002395:Catecholamines; D005230:Fatty Acids, Nonesterified; D005934:Glucagon; D009638:Norepinephrine; D006145:Guanethidine