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, 135 (5), 630-5

Antinociceptive Effects of Gabapentin & Its Mechanism of Action in Experimental Animal Studies

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Antinociceptive Effects of Gabapentin & Its Mechanism of Action in Experimental Animal Studies

Fatma Sultan Kilic et al. Indian J Med Res.

Abstract

Background & objectives: Several studies have shown the possible analgesic effects of gabapentin, widely used as an antiepileptic. Thus, clinical studies have been carried out especially for neuropathic syndroms. This study was undertaken to investigate experimentally whether gabapentin has analgesic effects in mice and rats.

Methods: The mice were divided into 10 groups (n=7) with various treatments to assess central and peripheral antinociceptive activity of gabapentin. Hot plate, tail clip and tail flick tests were applied for the investigation of central antinociceptive activity and the writhing test was applied for the investigation of peripheral antinociceptive activity. In addition, we also evaluated the levels of PGE 2 and nNOS on perfused hippocampus slices of rats.

Results: Gabapentin showed a peripheral antinociceptive effect at all doses and a central antinociceptive effect at 30mg/kg dose. While the L-NAME and cyproheptadine changed the central and peripheral effects of gabapentin, naloxone did not change these effects. In vitro studies showed that gabapentin significantly increased nNOS level. PGE 2 and nNOS were found to have an important role in the antinociceptive effects of gabapentin at all doses and its combinations with L-NAME, cyproheptadine, indomethacine, and naloxone. As expected, PGE 2 levels decreased in all groups, while nNOS levels increased, which is believed to be an adaptation mechanism.

Interpretation & conclusions: Our findings indicate that arachidonate, nitrergic and serotonergic systems play an important role in the antinociceptive activity of gabapentin except for the opioidergic system. Additionally, this effect occured centrally and peripherally. These effects were also mediated by nNOS and PGE2.

Figures

Fig. 1
Fig. 1
The peripheral antinociceptive activity with different doses of gabapentin (GBP). *P<0.05 compared to control group. Values are mean ± SEM (n=7).
Fig. 2
Fig. 2
The peripheral antinociceptive activity of gabapentin based on all groups. GBP, gabapentin; Cypro, cyproheptadine; L-Arg, L-arginine; Nalox, naloxone; L-NAME, L-nitro arginine methyl ester. *P<0.05 compared to control group. Values are mean ± SEM (n=7).
Fig. 3
Fig. 3
The central antinociceptive activity of gabapentin at different doses. GBP, gabapentin; %MPE, % maximal potent effect. *P<0.05 compared to control; +P<0.05 compared to gabapentin (30 mg/kg). Values are mean ± SEM (n=7).
Fig. 4
Fig. 4
The central antinociceptive activity in various groups. GBP, gabapentin; Cypro, cyproheptadine; L-Arg, L-arginine; Nalox, naloxone; L-NAME, L-nitro arginine methyl ester; %MPE, % maximal potent effect. *P<0.05 compared to control; +P<0.05 compared to gabapentin (30 mg/kg).

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References

    1. Dixit RK, Bhargava VK. Cholinergic mechanism in gabapentin analgesia. Indian J Pharmacol. 2001;33:221–2.
    1. Bensson JM. The neurobiology of pain. Lancet. 1999;353:1610–5. - PubMed
    1. Magnus L. Non epileptic uses of gabapentin. Epilepsia. 1999;40:66–74. - PubMed
    1. Lu Y, Westlund KN. Gabapentin attenuates nociceptive behaviors in an acute arthritis model in rats. J Pharmacol Exp Therp. 1999;290:214–9. - PubMed
    1. Moretti R, Antonello RM, Torre P, Cazzato G. Headache and neck pain: Gabapentin as a posible treatment. J Headache. 2000;1:155–61.

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