title: Assessment of the relationship between hyperalgesia and peripheral inflammation in magnesium-deficient rats.
abstract: Magnesium-deficient rats develop simultaneously a significant lowering of nociceptive threshold and a generalized inflammation. We investigated the relationship between these two phenomena by testing drugs that are able to suppress the inflammation in this model. In weaning rats fed a magnesium-depleted diet for ten days, the nociceptive threshold was assessed by the paw pressure test and the inflammation by a clinical score. A non-steroidal anti-inflammatory drug (piroxicam); antagonists of H1 and H2 receptors (astemizole and cimetidine. respectively); a glucocorticoid (dexamethasone); an inhibitor of mastocyte degranulation (cromoglycate); and estradiol benzoate were used to block the inflammatory response. Dexamethasone and estradiol significantly suppressed the inflammation (p < 0.001 vs control group). Cromoglycate showed a delayed anti-inflammatory effect (p < 0.01 vs control group on D10). The combination of astemizole and cimetidine partially blocked the inflammation process, whereas astemizole and piroxicam were without effect. Regardless of the effect of the test drugs on inflammation, no change in the time course of hyperalgesia was observed. These data support the view that hyperalgesia induced by the magnesium-depleted diet is not a consequence of the inflammatory process.
authors.affiliation: INSERM EMI 9904-Pharmacologie Fondamentale et Clinique de la Douleur, Laboratoire de Pharmacologie Médicale, Faculté de Médecine, Clermont-Ferrand, France.
authors.forename: Sophie
authors.initials: S
authors.lastname: Begon
authors.forename: Abdelkrim
authors.initials: A
authors.lastname: Alloui
authors.forename: Alain
authors.initials: A
authors.lastname: Eschalier
authors.forename: André
authors.initials: A
authors.lastname: Mazur
authors.forename: Yves
authors.initials: Y
authors.lastname: Rayssiguier
authors.forename: Claude
authors.initials: C
authors.lastname: Dubray
mesh_terms: D000818:Animals; D000893:Anti-Inflammatory Agents / Q000627:therapeutic use; D016589:Astemizole / Q000627:therapeutic use; D002927:Cimetidine / Q000627:therapeutic use; D004205:Cromolyn Sodium / Q000627:therapeutic use; D003907:Dexamethasone / Q000627:therapeutic use; D004195:Disease Models, Animal; D004958:Estradiol / Q000031:analogs & derivatives* / Q000627:therapeutic use; D006930:Hyperalgesia / Q000188:drug therapy / Q000209:etiology / Q000503:physiopathology*; D007249:Inflammation / Q000188:drug therapy / Q000209:etiology / Q000503:physiopathology*; D008275:Magnesium Deficiency / Q000150:complications / Q000503:physiopathology*; D008297:Male; D010894:Piroxicam / Q000627:therapeutic use; D051381:Rats; D017208:Rats, Wistar
chemical_list: D000893:Anti-Inflammatory Agents; D010894:Piroxicam; C074283:estradiol 3-benzoate; D004958:Estradiol; D016589:Astemizole; D003907:Dexamethasone; D002927:Cimetidine; D004205:Cromolyn Sodium