Results 121 to 130 of about 21,005 (156)

Structure—Activity Relationships for alpha-2 Adrenergic Receptor Agonists and Antagonists

1988
This chapter extends the discussion provided in Chapter 1 by providing an overview of the development of criteria for subclassification of alpha-adrenergic receptors into alpha-1 vs alpha-2 adrenergic receptor sybtypes and of more recent data suggesting the existence of subtypes of alpha-2 adrenergic receptors.
Robert R. Ruffolo, Robert M. DeMarinis, Margaret Wise, J. Paul Hieble   +3 more
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Mechanism of agonist and antagonist binding to .alpha.2 adrenergic receptors: evidence for a precoupled receptor-guanine nucleotide protein complex

Biochemistry, 1988
The alpha 2 adrenergic receptor (AR) inhibits adenylate cyclase via an interaction with Ni, a guanine nucleotide binding protein. The early steps involved in the activation of the alpha 2 AR by agonists and the subsequent interaction with Ni are poorly understood.
R R, Neubig, R D, Gantzos, W J, Thomsen
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Different sedimentation properties of agonist- and antagonist-labelled platelet alpha2 adrenergic receptors

Biochemical and Biophysical Research Communications, 1981
Abstract Alpha2 adrenergic receptors were solubilized from human platelet particulate preparations with digitonin. The solubilized alpha2 receptors retained the essential binding specificity characteristics of the membrane-bound receptors. The alpha2 receptors could be labelled in platelet membranes with either agonist ([3H]epinephrine) or antagonist
T, Michel, B B, Hoffman, R J, Lefkowitz, M G, Caron   +3 more
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p-[125I]iodoclonidine, a novel radiolabeled agonist for studying central alpha 2-adrenergic receptors.

Molecular Pharmacology, 1990
Unlabeled p-iodoclonidine was efficacious in attenuating forskolin-stimulated cAMP accumulation in SK-N-SH neuroblastoma cells. Maximal attenuation was 76 +/- 3%, with an EC50 of 347 +/- 60 nM. Comparable values of epinephrine were 72 +/- 3% and 122 +/- 22 nM. Responses to both agonists were abolished by 10 microM phentolamine.
B M, Baron, B W, Siegel
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[Adrenergic receptor and alpha 2 agonist--4: Applied and clinical pharmacology of alpha 2 agonist].

Masui. The Japanese journal of anesthesiology, 1997
Alpha 2 adrenergic agonists currently are used in the anesthetic management of the surgical patient for their sedative/hypnotic, anesthetic-sparing, analgesic, and sympatholytic properties. Experimental and clinical studies have progressed to the point where anesthesiologists are now focusing on the use of these agents for their analgesic and ...
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[Protective effect of adrenergic alpha 2-receptor agonists in hypoxic hypoxia].

Biulleten' eksperimental'noi biologii i meditsiny, 1986
The antihypoxic effect of alpha 2-adrenoceptor agonists was studied by two different approaches: reproduction of the effect by a number of alpha 2-agonists and its blockade with selective antagonists. The data obtained suggest that alpha 2-adrenoceptor agonists increase the survival and the lifespan of mice in all the models of acute hypoxic hypoxia ...
V I, Kulinskiĭ, I A, Ol'khovskiĭ, A N, Kovalevskiĭ   +2 more
openaire   +1 more source

Tight agonist binding may prevent the correct interpretation of agonist competition binding curves for alpha 2-adrenergic receptors.

Molecular Pharmacology, 1987
alpha 2-Adrenergic receptors in calf retina membranes can be specifically labeled with the tritiated antagonist 3H-RX 781094. Saturation binding occurs to a single class of noncooperative sites. The number of sites amounts to 1070 +/- 243 and 935 +/- 178 fmol/mg of protein, and the equilibrium dissociation constants equal 1.8 +/- 0.4 and 3.8 +/- 0.3 nM
A, Convents, J P, De Backer, D, Convents, G, Vauquelin   +3 more
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[Radiation-protective effect of agonists of alpha-2 adrenergic receptors. Methyldopa].

Radiatsionnaia biologiia, radioecologiia, 1997
MethylDOPA has the considerable (60-80%) and lasting RPE at both intraperitoneal (0.5-3.8 mmol/kg) and per os (3.8-7.1 mmol/kg) introduction in radiation dose 8 Gr (LD97/30). Optimal time for introduction is 0.5-3.0 hours intraperitoneally and 3-6 hours per os. Evidently, methylDOPA RPE is realized via alpha 2-adrenoceptors.
V I, Kulinskiĭ, V Iu, Kovtun, V G, Iashunskiĭ, A L, Klimova   +3 more
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GTP regulates binding of agonists to alpha 2-adrenergic receptors in human platelets.

Archives internationales de pharmacodynamie et de therapie, 1982
The potent alpha 2-adrenergic receptor antagonist 3H-yohimbine was used to characterize alpha-adrenergic receptors in human platelet membranes. Binding of 3H-yohimbine was at 25 degrees rapid (t 1/2 = 3 min) readily reversible (t 1/2 = 5.5 min), saturable with 221 +/- 38.9 fmoles bound/mg protein (N = 10) and of high affinity (KD = 1.97 nM). Inhibition
O E, Brodde, A, Hardung, H, Ebel, K D, Bock   +3 more
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The resolution of agonist alpha 2-adrenergic receptor complexes from unoccupied receptors or antagonist-alpha 2 receptor complexes using DEAE chromatography.

Journal of cyclic nucleotide and protein phosphorylation research, 1985
Alpha 2-adrenergic receptors linked to inhibition of adenylate cyclase activity in human platelet membranes can be isolated using DEAE chromatography following solubilization into digitonin-containing buffers. This procedure permits resolution of agonist-occupied receptors from antagonist-occupied receptors.
L E, Limbird, S T, MacMillan, D L, Kalinoski   +2 more
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