Anorectic effect of alpha 2-antagonists in dog: effect of acute and chronic treatment.
Acute oral administration of alpha 2-antagonists (yohimbine, RX 821002, atipamezole: 1 mg/kg each) reduced dog food intake. Yohimbine reduced food intake over 20 hours, while the effect of the two other drugs lasted only 2 hours. Yohimbine (0.4 or 1 microgram/kg) gave the same results. At these doses, it promoted a lasting durable increase in plasma nonesterified fatty acids and catecholamines levels and a transient elevation of plasma insulin levels. The beta-antagonist nadolol (4 mg/kg per os) suppressed the yohimbine-induced lipid mobilization without modifying its anorectic effect. Chronic oral yohimbine (0.4 mg/kg/day during 14 days) reduced food intake and promoted a weight loss. Normal food intake was recovered two days after yohimbine withdrawal. No change was observed in the number of platelet alpha 2-adrenergic receptors. In addition to their lipid mobilizing action and sympathetic tone stimulation, alpha 2-antagonist compounds reduce food intake.
Institut Nationnal de la Santé et de la Recherche Médicale (INSERM U 317), Laboratoire de Pharmacologie Médicale, Faculté de médecine, Toulouse, France.
M
M
Berlan
J
J
Galitzky
M A
MA
Tran
P
P
Montastruc
D000317:Adrenergic alpha-Antagonists / Q000494:pharmacology*; D000818:Animals; D001067:Appetite Depressants / Q000494:pharmacology*; D001786:Blood Glucose / Q000378:metabolism; D001792:Blood Platelets / Q000187:drug effects / Q000378:metabolism; D001835:Body Weight / Q000187:drug effects; D002395:Catecholamines / Q000097:blood; D002462:Cell Membrane / Q000187:drug effects / Q000378:metabolism; D004146:Dioxanes / Q000494:pharmacology; D004285:Dogs; D005230:Fatty Acids, Nonesterified / Q000097:blood; D005247:Feeding Behavior / Q000187:drug effects; D019329:Idazoxan / Q000031:analogs & derivatives; D007093:Imidazoles / Q000494:pharmacology; D007328:Insulin / Q000097:blood; D008297:Male; D009248:Nadolol / Q000494:pharmacology; D015016:Yohimbine / Q000494:pharmacology
D000317:Adrenergic alpha-Antagonists; D001067:Appetite Depressants; D001786:Blood Glucose; D002395:Catecholamines; D004146:Dioxanes; D005230:Fatty Acids, Nonesterified; D007093:Imidazoles; D007328:Insulin; C050701:atipamezole; D015016:Yohimbine; D009248:Nadolol; C058525:2-methoxyidazoxan; D019329:Idazoxan