Acute stress-induced antinociception is cGMP-dependent but heme oxygenase-independent

Author(s)

Carvalho-Costa, P. G. ^[1] ; Branco, L. G. S. ^[2] ; Leite-Panissi, C. R. A. ^{[1, 2]}

Affiliation

^[1] Univ Sao Paulo, Fac Filosofia Ciencias & Letras Ribeirao Preto, Programa Grad Psicobiol, BR-14040904 Ribeirao Preto, SP - Brazil

^[2] Univ Sao Paulo, Fac Odontol Ribeirao Preto, Dept Morfol Fisiol & Patol Basica, BR-14040904 Ribeirao Preto, SP - Brazil

• Document type: Journal article
• Source: Brazilian Journal of Medical and Biological Research; v. 47, n. 12, p. 1057-1061, DEC 2014.
• Web of Science Citations: 1

Abstract

Endogenous carbon monoxide (CO), which is produced by the enzyme heme oxygenase (HO), participates as a neuromodulator in physiological processes such as thermoregulation and nociception by stimulating the formation of 3′,5′-cyclic guanosine monophosphate (cGMP). In particular, the acute physical restraint-induced fever of rats can be blocked by inhibiting the enzyme HO. A previous study reported that the HO-CO-cGMP pathway plays a key phasic antinociceptive role in modulating noninflammatory acute pain. Thus, this study evaluated the involvement of the HO-CO-cGMP pathway in antinociception induced by acute stress in male Wistar rats (250-300 g; n=8/group) using the analgesia index (AI) in the tail flick test. The results showed that antinociception induced by acute stress was not dependent on the HO-CO-cGMP pathway, as neither treatment with the HO inhibitor ZnDBPG nor heme-lysinate altered the AI. However, antinociception was dependent on cGMP activity because pretreatment with the guanylate cyclase inhibitor 1H-[1,2,4] oxadiazolo [4,3-a] quinoxaline-1-one (ODQ) blocked the increase in the AI induced by acute stress. (AU)

• FAPESP's process: 07/08122-7 - HO-CO-cGMP pathway in the antinociception induced by stress in rats.
• Grantee: Christie Ramos Andrade Leite Panissi
• Support Opportunities: Regular Research Grants