title: Effects of salbutamol and BRL 37344 on diastolic arterial blood pressure, plasma glucose and plasma lactate in rabbits.
abstract: The aim of this study was to investigate in rabbits the diastolic arterial blood pressure, plasma glucose and plasma lactate responses to salbutamol (a selective beta-2 adrenoceptor agonist) and BRL 37344 (a selective beta-3 adrenoceptor agonist) in comparison with CGP 12177 (a potent beta-1 and beta-2 adrenoceptor antagonist which also acts as a partial beta-3 agonist), isoprenaline (a non-selective beta-1, beta-2 and beta-3 adrenoceptor agonist) and adrenaline (a non-selective beta and alpha adrenoceptor agonist). All drugs were iv infused at the same dose: 0.3 microgram/kg/min (30 min). In sodium pentobarbitone (40 mg/kg)-anasthetized animals none of these compounds altered diastolic arterial blood pressure. BRL 37344 (0.1, 0.3, 1 microgram/kg/min) did not modify this parameter either. In conscious 24-h fasted rabbits, only adrenaline was able to increase plasma glucose levels. By contrast, under the same experimental conditions, salbutamol, isoprenaline and adrenaline, but not BRL 37344 or CGP 12177, induced a significant increase in plasma lactate levels. Finally, the salbutamol-mediated plasma lactate response was inhibited in the presence of clonidine (2 micrograms/kg/min, an alpha-2 adrenoceptor agonist), a drug considered to have opposite effects (stimulatory and inhibitory) on the adenylate cyclase system. In conclusion, these data suggest that only beta-2 adrenoceptor stimulation is able to increase plasma lactate levels, a response which is inhibited by alpha-2 adrenoceptor stimulation.
authors.affiliation: Facultad de Medicina, Universidad de Salamanca, Spain.
authors.forename: M
authors.initials: M
authors.lastname: Reverte
authors.forename: J
authors.initials: J
authors.lastname: Moratinos
mesh_terms: D000318:Adrenergic beta-Agonists / Q000494:pharmacology*; D000420:Albuterol / Q000494:pharmacology*; D000818:Animals; D001786:Blood Glucose / Q000187:drug effects*; D001794:Blood Pressure / Q000187:drug effects*; D003000:Clonidine / Q000494:pharmacology; D004983:Ethanolamines / Q000494:pharmacology*; D007773:Lactates / Q000097:blood*; D019344:Lactic Acid; D008297:Male; D011817:Rabbits
chemical_list: D000318:Adrenergic beta-Agonists; D001786:Blood Glucose; D004983:Ethanolamines; D007773:Lactates; D019344:Lactic Acid; C057368:BRL 37344; D003000:Clonidine; D000420:Albuterol