Actual receptor mapping

The parameter (c) above aids in determining the precise location of the available receptor-occupied space with respect to the particular pharmacophore (i.e., actual receptor mapping). ... 

The nature of the cholinergic receptor has been the subject of considerable study for over 75 years. Aspects of its shape, conformations, and active sites have, over the years, slowly and enticingly revealed themselves to our prying. The efforts were initially by empirical-intuitive methods, then by SAR analogies, receptor mapping, and other indirect methods. Generous applications of X-ray crystallography and molecular receptor probes followed, and most recently, the actual isolation of the active receptor preparations were achieved. 

G. Calomme and P.J. Lewi, Multivariate analysis of structure-activity data. Spectral map of opioid narcotics in receptor binding. Actual. Chim. Therap., S.l 1 (1984) 121-126. 

It would have helped at that point if antibodies to the receptors could have been employed to map the location of the receptor subtypes by immunohistochemis-try. In retrospect, two factors stand out as confounding this and diverting the visualization of ARs along the alternative routes of epitope labeling and fluorescent ligand binding. These factors are apparent nonselectivity and actual heterogeneity, which may be different sides of the same coin. 

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