Colorectal distension-induced suppression of a nociceptive somatic reflex response in the rat: modulation by tissue injury or inflammation.
Inhibition of somatic nociception by conditioning noxious visceral stimulation was studied under pathophysiological conditions in rats. Viscero-somatic inhibition was enhanced following visceral inflammation and reduced by a somatic heat injury. The enhancement was reversed by an N-methyl-D-aspartate (NMDA) receptor antagonist. These changes in viscero-somatic inhibition may be explained by corresponding changes in excitatory drives evoked by conditioning and test stimulation, although disinhibition may contribute to reduction of inhibition following somatic injury.
Kalmari
Jaakko
J
Biomedicum Helsinki, Institute of Biomedicine/Physiology, University of Helsinki, 00014, Finland.
Pertovaara
Antti
A
D000818:Animals; D002056:Burns / Q000503:physiopathology*; D003092:Colitis / Q000503:physiopathology; D003106:Colon / Q000294:innervation / Q000503:physiopathology*; D003213:Conditioning, Psychological / Q000502:physiology; D016291:Dizocilpine Maleate / Q000494:pharmacology; D015536:Down-Regulation / Q000502:physiology; D018691:Excitatory Amino Acid Antagonists / Q000494:pharmacology; D006930:Hyperalgesia / Q000503:physiopathology; D007249:Inflammation / Q000139:chemically induced / Q000503:physiopathology*; D008297:Male; D009433:Neural Inhibition / Q000187:drug effects / Q000502:physiology*; D009619:Nociceptors / Q000502:physiology; D010146:Pain / Q000503:physiopathology*; D010812:Physical Stimulation / Q000379:methods; D051381:Rats; D017208:Rats, Wistar; D011930:Reaction Time / Q000502:physiology; D016194:Receptors, N-Methyl-D-Aspartate / Q000037:antagonists & inhibitors / Q000378:metabolism; D012007:Rectum / Q000294:innervation / Q000503:physiopathology*; D012018:Reflex / Q000502:physiology*; D012867:Skin / Q000294:innervation / Q000503:physiopathology; D009435:Synaptic Transmission / Q000187:drug effects / Q000502:physiology; D017833:Visceral Afferents / Q000187:drug effects / Q000503:physiopathology
D018691:Excitatory Amino Acid Antagonists; D016194:Receptors, N-Methyl-D-Aspartate; D016291:Dizocilpine Maleate