Hormone receptor-coupling factor-adenylate cyclase interaction: theoretical considerations.

J J Blum

doi:10.1016/s0022-5193(84)80239-8

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Hormone receptor-coupling factor-adenylate cyclase interaction: theoretical considerations.

J J Blum

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Abstract

The steady-state response properties of two current models for receptor/nucleotide coupling protein/adenylate cyclase systems are examined by computer modeling techniques. In the model of Levitzki (Trends Pharmac. Sci., May, 1982, pp. 203-208), a ligand may give rise to full or partial agonist behavior only. In the model of Stadel, DeLean, and Lefkowitz (1982) configurations of the rate constants can be found which lead not only to full or partial agonist behavior, but also to varying degrees of inhibition at sufficiently high concentrations of ligand, as observed experimentally in a variety of adenylate cyclase systems. In the latter model, it is also possible to find configurations of the rate constants for which addition of a ligand will lead to inhibition of adenylate cyclase activity. The nature of partial agonism and reasons as to why it may be expected to occur for a wide variety of ligands are discussed.

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Adenylyl Cyclases Adrenergic beta-Agonists Adrenergic beta-Antagonists Animals GTP-Binding Proteins Guanosine Triphosphate Kinetics Ligands Models, Biological Receptors, Adrenergic, beta Receptors, Cell Surface Journal Article Research Support, U.S. Gov't, P.H.S.

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J J Blum. 1984-12-07. Hormone receptor-coupling factor-adenylate cyclase interaction: theoretical considerations.. https://doi.org/10.1016/s0022-5193(84)80239-8

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