title: Adenosine triphosphate as a stimulant for nociceptive and non-nociceptive muscle group IV receptors in the rat.
abstract: For cutaneous and articular nociceptors, adenosine triphosphate (ATP) has been shown to be an effective stimulant. The aim of present study was to find out if among muscle afferents ATP-sensitive group IV receptors are present, and if differences in ATP-responsiveness existed between nociceptive and non-nociceptive units. Single fibre activity was recorded from group IV afferents innervating the rat gastrocnemius-soleus muscle. Using mechanical stimuli the fibres were classified as nociceptive or non-nociceptive ones. ATP was injected intramuscularly into the receptive field of the fibre. Results were: (1) ATP at a concentration that is present in muscle cells elicited excitations in 67% of the fibres; (2) ATP excited both nociceptive and non-nociceptive receptors; and (3) the acidity of the ATP solution was not an important factor for the ATP effect.
authors.affiliation: Institut für Anatomie und Zellbiologie, Universität Heidelberg, Im Neuenheimer Feld 307, D-69120 Heidelberg, Germany.
authors.forename: Jochen
authors.initials: J
authors.lastname: Reinöhl
authors.forename: Ulrich
authors.initials: U
authors.lastname: Hoheisel
authors.forename: Thomas
authors.initials: T
authors.lastname: Unger
authors.forename: Siegfried
authors.initials: S
authors.lastname: Mense
mesh_terms: D000200:Action Potentials / Q000187:drug effects / Q000502:physiology; D000255:Adenosine Triphosphate / Q000494:pharmacology*; D000818:Animals; D008297:Male; D018482:Muscle, Skeletal / Q000187:drug effects* / Q000502:physiology; D036421:Nerve Fibers, Unmyelinated / Q000187:drug effects / Q000502:physiology; D009619:Nociceptors / Q000502:physiology; D051381:Rats; D017207:Rats, Sprague-Dawley; D018048:Receptors, Purinergic P2 / Q000502:physiology*; D058848:Receptors, Purinergic P2X4
chemical_list: C548228:P2rx4 protein, rat; D018048:Receptors, Purinergic P2; D058848:Receptors, Purinergic P2X4; D000255:Adenosine Triphosphate