Agonist-receptor complex

The basis of this model is the experimental fact that most agonist dose-response curves are hyperbolic in nature. The reasoning for making this assumption is as follows. If agonist binding is governed by mass action, then the relationship between the agonist-receptor complex and response must either be linear or hyperbolic as well. Response is thus defined as... 

Also, mass action defines the concentration of agonist-receptor complex as... 

Assuming a hyperbolic relationship between response and the amount of agonist-receptor complex, response is defined as... 

The equilibrium dissociation constant of the agonist-receptor complex (Ka) can be obtained by a regression of 1/[A] upon 1/[A7]. This leads to a linear regression from which... 

KA = Equilibrium dissociation constant of agonist-receptor complex. 

Kx, standard pharmacologic convention for the equilibrium dissociation constant of an agonist-receptor complex with units of M. It is the concentration that occupies half the receptor population at equilibrium. It also can be thought of as the reciprocal of affinity. 

Here, the agonist-receptor complex (AR) combines with a G-protein (G) to form a ternary complex (ARG ), which can initiate further cellular events, such as the activation of adenylate cyclase. However, this simple scheme (the ternary complex model) was not in keeping with what was already known about the importance of isomerization in receptor activation (see Sections 1.2.3 and 1.4.3), and it also failed to account for findings that were soon to come from studies of mutated receptors. In all current models of G-protein-coupled receptors, receptor activation by isomerization is assumed to occur so that the model becomes ... 

Blockade of this important signal transduction pathway leads to impaired ability of neurons to respond to activation of membrane receptors for transmitters or other chemical signals. Another site of action of lithium may be GTP-binding proteins responsible for signal transduction initiated by formation of the agonist-receptor complex. 

Agonist + Receptor Agonist-Receptor complex r A S ridsoon ... 

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