TY - JOUR T1 - Studies on the Noradrenaline α-Receptor JF - Molecular Pharmacology JO - Mol Pharmacol SP - 28 LP - 36 VL - 3 IS - 1 AU - M. MAY AU - J. F. MORAN AU - H. KIMELBERG AU - D. J. TRIGGLE Y1 - 1967/01/01 UR - http://molpharm.aspetjournals.org/content/3/1/28.abstract N2 - The rates of recovery of response of rabbit aortic strips, blocked with N,N-dimethyl-2-bromo-2-phenylethylamine, to noradrenaline, adrenaline, N-ethyl- and N-isopropyl-noradrenaline have been determined. The close similarities of these recovery rates suggests that "spare" receptors are of little significance in this system. The use of 3H-labeled N,N-dimethyl-2-bromo-2-phenylethylamine enabled an estimate of the concentration of α-receptors, 1.15 x 1012 receptors per milligram of tissue dry weight, to be made and also provided good evidence for the view that tissue response is proportional to the concentration of agonist-receptor complex. ACKNOWLEDGMENTS The authors wish to acknowledge the assistance of Miss Marlene Calderone. This investigation was supported by a grant from the National Institute of Health, U. S. Public Health Service (GM 11603). ER -