TY - JOUR T1 - Investigation into the Association between Serotonin and Adenosine Triphosphate <em>in Vitro</em> by Nuclear Magnetic Resonance and Ultraviolet Spectroscopy JF - Molecular Pharmacology JO - Mol Pharmacol SP - 565 LP - 574 VL - 8 IS - 5 AU - THOMAS NOGRADY AU - PAVEL D. HRDINA AU - GEORGE M. LING Y1 - 1972/09/01 UR - http://molpharm.aspetjournals.org/content/8/5/565.abstract N2 - Adenosine triphosphate and serotonin (5-hydroxytryptamine, 5-HT) form micellar complexes in synaptic storage vesicles and blood platelets. The interaction of ATP with 5-HT and the binding forces responsible for micelle formation were investigated by nuclear magnetic resonance and ultraviolet spectroscopy in vitro. The principal bond is an ionic interaction between the side chain amino group of 5-HT and the negatively charged phosphate of ATP. This results in the disruption of ATP stacking and overlap of the indole and adenine moiety, forming a contact charge-transfer complex with a low apparent association constant. pH and ionic strength effects on complex formation were also investigated. ACKNOWLEDGMENTS The valuable help of Dr. M. Hogben of the Chemistry Department, Loyola College, in the computer simulation of 5-HT spectra and calculation of linewidths is gratefully acknowledged. ER -