Chronic treatment with agonists of beta(2)-adrenergic receptors in neuropathic pain.
Expression of beta(2)-adrenoceptors (beta(2)-ARs) within the nociceptive system suggested their potential implication in nociception and pain. Recently, we demonstrated that these receptors are essential for neuropathic pain treatment by antidepressant drugs. The aim of the present study was to investigate whether the stimulation of beta(2)-ARs could in fact be adequate to alleviate neuropathic allodynia. Neuropathy was induced in mice by sciatic nerve cuffing. We demonstrate that chronic but not acute stimulation of beta(2)-ARs with agonists such as clenbuterol, formoterol, metaproterenol and procaterol suppressed neuropathic allodynia. By using a pharmacological approach with the beta(2)-AR antagonist ICI 118,551 or a transgenic approach with mice deficient for beta(2)-ARs, we confirmed that the antiallodynic effect of these agonists was specifically related to their action on beta(2)-ARs. We also showed that chronic treatment with the beta(1)-AR agonist xamoterol or with the beta(3)-AR agonist BRL 37344 had no effect on neuropathic allodynia. Chronic stimulation of beta(2)-ARs, but not beta(1)- or beta(3)-ARs, by specific agonists is thus able to alleviate neuropathic allodynia. This action of beta(2)-AR agonists might implicate the endogenous opioid system; indeed chronic clenbuterol effect can be acutely blocked by the delta-opioid receptor antagonist naltrindole. Present results show that beta(2)-ARs are not only essential for the antiallodynic action of antidepressant drugs on sustained neuropathic pain, but also that the stimulation of these receptors is sufficient to relieve neuropathic allodynia in a murine model. Our data suggest that beta(2)-AR agonists may potentially offer an alternative therapy to antidepressant drugs for the chronic treatment of neuropathic pain.
Institut des Neurosciences Cellulaires et Intégratives, Centre National de la Recherche Scientifique, Strasbourg, France.
Ipek
I
Yalcin
Luc-Henri
LH
Tessier
Nathalie
N
Petit-Demoulière
Elisabeth
E
Waltisperger
Lutz
L
Hein
Marie-José
MJ
Freund-Mercier
Michel
M
Barrot
D058666:Adrenergic beta-2 Receptor Agonists; D000318:Adrenergic beta-Agonists / Q000494:pharmacology* / Q000627:therapeutic use; D000319:Adrenergic beta-Antagonists / Q000494:pharmacology; D000818:Animals; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D004334:Drug Administration Schedule; D004347:Drug Interactions; D007839:Functional Laterality; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D009271:Naltrexone / Q000031:analogs & derivatives / Q000494:pharmacology; D009292:Narcotic Antagonists / Q000494:pharmacology; D010147:Pain Measurement / Q000379:methods; D017288:Pain Threshold / Q000187:drug effects* / Q000502:physiology; D011412:Propanolamines / Q000494:pharmacology; D018343:Receptors, Adrenergic, beta-2 / Q000172:deficiency; D012585:Sciatica / Q000188:drug therapy / Q000503:physiopathology*; D013997:Time Factors
D058666:Adrenergic beta-2 Receptor Agonists; D000318:Adrenergic beta-Agonists; D000319:Adrenergic beta-Antagonists; D009292:Narcotic Antagonists; D011412:Propanolamines; D018343:Receptors, Adrenergic, beta-2; C026777:ICI 118551; D009271:Naltrexone; C055382:naltrindole