Biomaterial Database

Adrenoceptor of the alpha 2-subtype mediating inhibition of the human fat cell adenylate cyclase. 1981

H Kather, and B Simon

In an attempt to characterize the adenylate cyclase-coupled alpha-adrenoceptors of human fat cells the effects of various alpha-adrenergic agonists and antagonists were examined in the presence of 0.05 mmol/l of propranolol. The order of agonist potencies with respect to alpha-adrenergic inhibition was (-)-adrenaline greater than alpha-methyl-(-)-noradrenaline greater than (-)-phenylephrine with half-maximal inhibition occurring at 2 mumol/l of (-)-adrenaline and 7 mumol/l of alpha-methyl-(-)-noradrenaline respectively. The inhibition of adenylate cyclase induced by 0.05 mmol/l of (-)-adrenaline was reversed by the alpha-blocking agents yohimbine and prazosin, with the alpha 2-site-directed antagonist yohimbine being more than 100-times more potent than prazosin which is more active at alpha 1-sites. The results show that the cyclase-coupled alpha-adrenoceptors of human fat cells, which probably represent the physiologically relevant target of antilipolytic catecholamine effects, display characteristic features of the alpha 2-adrenoceptor subtype.

UI	MeSH Term	Description	Entries
D011941	Receptors, Adrenergic	Cell-surface proteins that bind epinephrine and/or norepinephrine with high affinity and trigger intracellular changes. The two major classes of adrenergic receptors, alpha and beta, were originally discriminated based on their cellular actions but now are distinguished by their relative affinity for characteristic synthetic ligands. Adrenergic receptors may also be classified according to the subtypes of G-proteins with which they bind; this scheme does not respect the alpha-beta distinction.	Adrenergic Receptors,Adrenoceptor,Adrenoceptors,Norepinephrine Receptor,Receptors, Epinephrine,Receptors, Norepinephrine,Adrenergic Receptor,Epinephrine Receptors,Norepinephrine Receptors,Receptor, Adrenergic,Receptor, Norepinephrine
D011942	Receptors, Adrenergic, alpha	One of the two major pharmacological subdivisions of adrenergic receptors that were originally defined by the relative potencies of various adrenergic compounds. The alpha receptors were initially described as excitatory receptors that post-junctionally stimulate SMOOTH MUSCLE contraction. However, further analysis has revealed a more complex picture involving several alpha receptor subtypes and their involvement in feedback regulation.	Adrenergic alpha-Receptor,Adrenergic alpha-Receptors,Receptors, alpha-Adrenergic,alpha-Adrenergic Receptor,alpha-Adrenergic Receptors,Receptor, Adrenergic, alpha,Adrenergic alpha Receptor,Adrenergic alpha Receptors,Receptor, alpha-Adrenergic,Receptors, alpha Adrenergic,alpha Adrenergic Receptor,alpha Adrenergic Receptors,alpha-Receptor, Adrenergic,alpha-Receptors, Adrenergic
D002395	Catecholamines	A general class of ortho-dihydroxyphenylalkylamines derived from TYROSINE.	Catecholamine,Sympathin,Sympathins
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000262	Adenylyl Cyclases	Enzymes of the lyase class that catalyze the formation of CYCLIC AMP and pyrophosphate from ATP.	Adenyl Cyclase,Adenylate Cyclase,3',5'-cyclic AMP Synthetase,Adenylyl Cyclase,3',5' cyclic AMP Synthetase,AMP Synthetase, 3',5'-cyclic,Cyclase, Adenyl,Cyclase, Adenylate,Cyclase, Adenylyl,Cyclases, Adenylyl,Synthetase, 3',5'-cyclic AMP
D000273	Adipose Tissue	Specialized connective tissue composed of fat cells (ADIPOCYTES). It is the site of stored FATS, usually in the form of TRIGLYCERIDES. In mammals, there are two types of adipose tissue, the WHITE FAT and the BROWN FAT. Their relative distributions vary in different species with most adipose tissue being white.	Fatty Tissue,Body Fat,Fat Pad,Fat Pads,Pad, Fat,Pads, Fat,Tissue, Adipose,Tissue, Fatty
D000316	Adrenergic alpha-Agonists	Drugs that selectively bind to and activate alpha adrenergic receptors.	Adrenergic alpha-Receptor Agonists,alpha-Adrenergic Receptor Agonists,Adrenergic alpha-Agonist,Adrenergic alpha-Receptor Agonist,Receptor Agonists, Adrenergic alpha,Receptor Agonists, alpha-Adrenergic,alpha-Adrenergic Agonist,alpha-Adrenergic Agonists,alpha-Adrenergic Receptor Agonist,Adrenergic alpha Agonist,Adrenergic alpha Agonists,Adrenergic alpha Receptor Agonist,Adrenergic alpha Receptor Agonists,Agonist, Adrenergic alpha-Receptor,Agonist, alpha-Adrenergic,Agonist, alpha-Adrenergic Receptor,Agonists, Adrenergic alpha-Receptor,Agonists, alpha-Adrenergic,Agonists, alpha-Adrenergic Receptor,Receptor Agonist, alpha-Adrenergic,Receptor Agonists, alpha Adrenergic,alpha Adrenergic Agonist,alpha Adrenergic Agonists,alpha Adrenergic Receptor Agonist,alpha Adrenergic Receptor Agonists,alpha-Agonist, Adrenergic,alpha-Agonists, Adrenergic,alpha-Receptor Agonist, Adrenergic,alpha-Receptor Agonists, Adrenergic
D000317	Adrenergic alpha-Antagonists	Drugs that bind to but do not activate alpha-adrenergic receptors thereby blocking the actions of endogenous or exogenous adrenergic agonists. Adrenergic alpha-antagonists are used in the treatment of hypertension, vasospasm, peripheral vascular disease, shock, and pheochromocytoma.	Adrenergic alpha-Receptor Blockaders,alpha-Adrenergic Blocking Agents,alpha-Adrenergic Receptor Blockaders,alpha-Blockers, Adrenergic,Adrenergic alpha-Blockers,alpha-Adrenergic Antagonists,alpha-Adrenergic Blockers,Adrenergic alpha Antagonists,Adrenergic alpha Blockers,Adrenergic alpha Receptor Blockaders,Agents, alpha-Adrenergic Blocking,Antagonists, alpha-Adrenergic,Blockaders, Adrenergic alpha-Receptor,Blockaders, alpha-Adrenergic Receptor,Blockers, alpha-Adrenergic,Blocking Agents, alpha-Adrenergic,Receptor Blockaders, alpha-Adrenergic,alpha Adrenergic Antagonists,alpha Adrenergic Blockers,alpha Adrenergic Blocking Agents,alpha Adrenergic Receptor Blockaders,alpha Blockers, Adrenergic,alpha-Antagonists, Adrenergic,alpha-Receptor Blockaders, Adrenergic