Biomaterial Database

Thermoregulatory responses to beta-adrenergic agonists at low ambient temperatures in the rat. 1993

H J Carlisle, and M J Stock

Department of Psychology, University of California, Santa Barbara 93106.

Dose-response effects on heat production (HP) and dry heat loss (DHL) following injection with the non-selective (beta 1/beta 2) adrenergic agonist isoprenaline (ISO) and the atypical B3 agonist BRL 35135 (BRL) were established at an ambient temperature of 25 degrees C in rats. Subsequently, the effects of HP and DHL of a maximal thermogenic dose of ISO (75 micrograms/kg) and a supramaximal dose of BRL (40 micrograms/kg) were tested at ambient temperatures of 5, 10 and 15 degrees C. In terms of heat production, BRL was no different from saline at 5 degrees C, but its thermogenic activity became increasingly evident as ambient temperature increased. For ISO, HP was lower than, or no different from, saline at 5 and 10 degrees C, respectively, but DHL exceeded HP at both temperatures, and colonic temperature fell significantly; ISO and BRL responses were similar at 15 degrees C. ISO was also capable of producing a decrease in HP at 10 degrees C if the rats were shaven. Substitution for endogenous, sympathetically mediated thermogenesis would explain the attenuation of the BRL and ISO effects at cool ambient temperatures, whereas the hypothermic effects of ISO in the cold appeared to be due to an inappropriate increase in DHL, which was exacerbated at 5 degrees C by a reduction in HP below saline values. The increase in DHL was consistent with beta 2-mediated effects of ISO on peripheral blood flow, but the mechanism responsible for the reduction in HP in the cold is unknown, although reduced vascular thermogenesis has been offered as a putative explanation.

UI	MeSH Term	Description	Entries
D007545	Isoproterenol	Isopropyl analog of EPINEPHRINE; beta-sympathomimetic that acts on the heart, bronchi, skeletal muscle, alimentary tract, etc. It is used mainly as bronchodilator and heart stimulant.	Isoprenaline,Isopropylarterenol,4-(1-Hydroxy-2-((1-methylethyl)amino)ethyl)-1,2-benzenediol,Euspiran,Isadrin,Isadrine,Isopropyl Noradrenaline,Isopropylnoradrenaline,Isopropylnorepinephrine,Isoproterenol Hydrochloride,Isoproterenol Sulfate,Isuprel,Izadrin,Norisodrine,Novodrin,Hydrochloride, Isoproterenol,Noradrenaline, Isopropyl,Sulfate, Isoproterenol
D008297	Male		Males
D008954	Models, Biological	Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.	Biological Model,Biological Models,Model, Biological,Models, Biologic,Biologic Model,Biologic Models,Model, Biologic
D010627	Phenethylamines	A group of compounds that are derivatives of beta- aminoethylbenzene which is structurally and pharmacologically related to amphetamine. (From Merck Index, 11th ed)	Phenylethylamines
D011943	Receptors, Adrenergic, beta	One of two major pharmacologically defined classes of adrenergic receptors. The beta adrenergic receptors play an important role in regulating CARDIAC MUSCLE contraction, SMOOTH MUSCLE relaxation, and GLYCOGENOLYSIS.	Adrenergic beta-Receptor,Adrenergic beta-Receptors,Receptors, beta-Adrenergic,beta Adrenergic Receptor,beta-Adrenergic Receptor,beta-Adrenergic Receptors,Receptor, Adrenergic, beta,Adrenergic Receptor, beta,Adrenergic beta Receptor,Adrenergic beta Receptors,Receptor, beta Adrenergic,Receptor, beta-Adrenergic,Receptors, beta Adrenergic,beta Adrenergic Receptors,beta-Receptor, Adrenergic,beta-Receptors, Adrenergic
D001833	Body Temperature Regulation	The processes of heating and cooling that an organism uses to control its temperature.	Heat Loss,Thermoregulation,Regulation, Body Temperature,Temperature Regulation, Body,Body Temperature Regulations,Heat Losses,Loss, Heat,Losses, Heat,Regulations, Body Temperature,Temperature Regulations, Body,Thermoregulations
D002001	Adipose Tissue, Brown	A thermogenic form of adipose tissue composed of BROWN ADIPOCYTES. It is found in newborns of many species including humans, and in hibernating mammals. Brown fat is richly vascularized, innervated, and densely packed with MITOCHONDRIA which can generate heat directly from the stored lipids.	Brown Fat,Hibernating Gland,Brown Adipose Tissue,Fat, Brown,Tissue, Brown Adipose
D003080	Cold Temperature	An absence of warmth or heat or a temperature notably below an accustomed norm.	Cold,Cold Temperatures,Temperature, Cold,Temperatures, Cold
D000318	Adrenergic beta-Agonists	Drugs that selectively bind to and activate beta-adrenergic receptors.	Adrenergic beta-Receptor Agonists,beta-Adrenergic Agonists,beta-Adrenergic Receptor Agonists,Adrenergic beta-Agonist,Adrenergic beta-Receptor Agonist,Betamimetics,Receptor Agonists, beta-Adrenergic,Receptors Agonists, Adrenergic beta,beta-Adrenergic Agonist,beta-Adrenergic Receptor Agonist,Adrenergic beta Agonist,Adrenergic beta Agonists,Adrenergic beta Receptor Agonist,Adrenergic beta Receptor Agonists,Agonist, Adrenergic beta-Receptor,Agonist, beta-Adrenergic,Agonist, beta-Adrenergic Receptor,Agonists, Adrenergic beta-Receptor,Agonists, beta-Adrenergic,Agonists, beta-Adrenergic Receptor,Receptor Agonist, beta-Adrenergic,Receptor Agonists, beta Adrenergic,beta Adrenergic Agonist,beta Adrenergic Agonists,beta Adrenergic Receptor Agonist,beta Adrenergic Receptor Agonists,beta-Agonist, Adrenergic,beta-Agonists, Adrenergic,beta-Receptor Agonist, Adrenergic,beta-Receptor Agonists, Adrenergic
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia