title: Zn2+ potentiates excitatory action of ATP on mammalian neurons.
abstract: Despite the increasing recognition that ATP is an important extracellular excitatory mediator in the nervous system, the regulation of ATP receptors is poorly understood. Because the extracellular Zn2+ concentration is regulated in a variety of biological tissues, we studied modulation of the ATP-gated cation channel by Zn2+ in mammalian neurons using the whole-cell patch-clamp technique. In approximately 73% of cells tested, the amplitude of ATP-activated membrane ion current increased up to 5-fold in the presence of micromolar concentrations of Zn2+. The characteristics of this action suggest that Zn2+ increases the apparent affinity of the receptor for ATP. In addition, Zn2+ increased membrane depolarization and action potential firing elicited by ATP. These observations suggest that Zn2+ may play a physiological role in regulating the excitatory action of ATP on mammalian neurons.
authors.affiliation: Laboratory of Molecular and Cellular Neurobiology, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Rockville, MD 20852.
authors.forename: C
authors.initials: C
authors.lastname: Li
authors.forename: R W
authors.initials: RW
authors.lastname: Peoples
authors.forename: Z
authors.initials: Z
authors.lastname: Li
authors.forename: F F
authors.initials: FF
authors.lastname: Weight
mesh_terms: D000255:Adenosine Triphosphate / Q000494:pharmacology*; D000818:Animals; D004305:Dose-Response Relationship, Drug; D004357:Drug Synergism; D005728:Ganglia, Sympathetic / Q000502:physiology*; D066298:In Vitro Techniques; D007473:Ion Channels / Q000187:drug effects / Q000502:physiology; D008297:Male; D008564:Membrane Potentials / Q000187:drug effects; D009474:Neurons / Q000187:drug effects / Q000502:physiology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D015032:Zinc / Q000494:pharmacology*
chemical_list: D007473:Ion Channels; D000255:Adenosine Triphosphate; D015032:Zinc