Mechanism by which peripheral galanin increases acute inflammatory pain.
Galanin (GAL) is a neuropeptide involved in pain transmission. Intraplantar GAL at low doses enhances capsaicin (CAP)-induced pain behaviors in rat, suggesting an excitatory role for GAL under acute inflammatory conditions. The mechanisms underlying this pro-nociceptive action have not yet been elucidated. Thus, the present study investigated the role of protein kinase C (PKC) in the GAL enhancement of CAP-induced inflammatory pain. Ipsilateral, but not contralateral, calphostin C, a PKC inhibitor, blocked GAL-induced potentiation of CAP-evoked inflammatory pain in a dose-dependent fashion. Peripheral activation of PKC using the phorbol ester phorbol-12-myristate-13-acetate (PMA) mimicked the pro-nociceptive effect of GAL. These results suggest that GAL enhances acute inflammatory pain through activation of PKC intracellular pathways.
Jimenez-Andrade
Juan Miguel
JM
Seccion Externa de Farmacologia, Centro de Investigacion y de Estudios Avanzados del Instituto Politecnico Nacional, Mexico, D.F., Mexico.
Zhou
Shengtai
S
Yamani
Ammar
A
Valencia de Ita
Sandra
S
Castañeda-Hernandez
Gilberto
G
Carlton
Susan M
SM
D000818:Animals; D002211:Capsaicin; D004305:Dose-Response Relationship, Drug; D004347:Drug Interactions; D004791:Enzyme Inhibitors / Q000494:pharmacology; D007839:Functional Laterality; D019004:Galanin / Q000008:administration & dosage*; D007249:Inflammation / Q000209:etiology; D008297:Male; D009281:Naphthalenes / Q000494:pharmacology; D010146:Pain / Q000139:chemically induced* / Q000150:complications; D010147:Pain Measurement / Q000379:methods; D015240:Phorbol 12,13-Dibutyrate / Q000494:pharmacology; D011493:Protein Kinase C / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D013997:Time Factors
D004791:Enzyme Inhibitors; D009281:Naphthalenes; C061465:calphostin complex; D015240:Phorbol 12,13-Dibutyrate; D019004:Galanin; D011493:Protein Kinase C; D002211:Capsaicin