Molecular Pharmacology, Vol 13, 615-620, Copyright © 1977 by the American Society for Pharmacology and Experimental Therapeutics

Interactions of Biogenic Amines with Organic Phosphate: A Proposed Model in Vitro for Study of Biological Interactions by ³¹P Nuclear Magnetic Resonance

¹ Mid-Atlantic Research Institute, Bethesda, Maryland 20014
² Microanalytical Services and Instrumentation Section, Laboratory of Chemistry, National Institute of Arthritis, Metabolism, and Digestive Diseases, National Institutes of Health, Bethesda, Maryland 20014

The interaction between ³¹P-containing substrates, 4-deoxypyridoxine phosphate and monomethyl phosphate, and a series of protonated biogenic amines has been quantitated by use of [³¹P]-¹H nuclear magnetic double resonance and titration. The difference in the phosphorus chemical shifts with and without amine in deuterated water indicated that optimal biogenic amine-phosphate interaction appears to require the presence of both a catechol ring and a -hydroxyl group in the ethylamine side chain. This is in good agreement with pharmacological measurements in vitro of biogenic amine retention by storage vesicles of rat heart adrenergic nerve terminals, indicating that phosphate could be involved in binding of biogenic amines in these vesicles. The model in vitro presented could provide a rapid, efficient method for biological evaluation of various drug-receptor systems involving phosphate-amine interactions.

Note:
ACKNOWLEDGMENTS We thank Drs. C. R. Creveling, J. Daly, and I. Kopin for useful comments and discussions, and Mrs. L. Weber and S. Paper for their assistance in manuscript preparation.