Role of the sympathetic nervous system during the development of obesity-induced hypertension in rabbits.
We have previously reported that weight gain induced by high-fat diet (HFD) leads to an increase in mean arterial pressure (MAP, +14%) and heart rate (HR, +31%) in the adult rabbit. In the present study, we tested the hypothesis that an increased activity of the sympathetic nervous system may contribute to the development of obesity-induced hypertension. A combination of alpha- and beta-adrenergic blockers (terazosin + propranolol) was chronically administered to rabbits housed in metabolic cages for continuous monitoring of arterial pressure by telemetry, 24 h a day. After 2 weeks of adrenergic blockade under control diet, animals were switched to HFD for the next 6 weeks. HFD induced a progressive increase in body weight, but no increase in mean arterial pressure (+0.2+/-2.5%) and a slight increase in heart rate (+14+/-3%). Time-control animals fed normal diet showed no changes in MAP or HR with long-term alpha- and beta-adrenergic blockade. Our results indicate that the activation of the sympathetic nervous system may play an important role in the pathogenesis of obesity-induced hypertension.
Antic
V
V
Institute of Physiology, University of Fribourg, Switzerland.
Kiener-Belforti
F
F
Tempini
A
A
Van Vliet
B N
BN
Montani
J P
JP
D000317:Adrenergic alpha-Antagonists / Q000494:pharmacology; D000319:Adrenergic beta-Antagonists / Q000494:pharmacology; D000818:Animals; D001794:Blood Pressure / Q000187:drug effects / Q000502:physiology; D001795:Blood Pressure Determination / Q000379:methods; D004041:Dietary Fats / Q000633:toxicity; D005919:Glomerular Filtration Rate / Q000187:drug effects; D006339:Heart Rate / Q000187:drug effects / Q000502:physiology; D006973:Hypertension / Q000188:drug therapy / Q000209:etiology* / Q000503:physiopathology; D007275:Injections, Intravenous; D007668:Kidney / Q000187:drug effects / Q000503:physiopathology; D008297:Male; D009765:Obesity / Q000139:chemically induced / Q000150:complications*; D010656:Phenylephrine / Q000008:administration & dosage; D011224:Prazosin / Q000031:analogs & derivatives / Q000494:pharmacology; D011433:Propranolol / Q000494:pharmacology; D011817:Rabbits; D012964:Sodium / Q000652:urine; D013564:Sympathetic Nervous System / Q000187:drug effects / Q000503:physiopathology*; D013566:Sympathomimetics / Q000008:administration & dosage; D013686:Telemetry
D000317:Adrenergic alpha-Antagonists; D000319:Adrenergic beta-Antagonists; D004041:Dietary Fats; D013566:Sympathomimetics; D010656:Phenylephrine; C041226:Terazosin; D012964:Sodium; D011433:Propranolol; D011224:Prazosin