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Preventive Treatment with Ketamine Attenuates the Ischaemia-Reperfusion Response in a Chronic Postischaemia Pain Model.

Liman S, Cheung CW, Wong KL, Tai W, Qiu Q, Ng KF, Choi SW, Irwin M - Oxid Med Cell Longev (2015)

Bottom Line: Ketamine treated rats showed a significantly lower temperature in the ischaemic hindpaw compared to saline (P < 0.01) and methylprednisolone (P < 0.05) groups.Mechanical and cold allodynia were significantly lower in the ischaemic side in the ketamine group (P < 0.05).In conclusion, immediate administration of ketamine after an ischaemia-reperfusion injury can alleviate pain and inflammation in the CPIP model and has potential to treat postischaemic pain.

View Article: PubMed Central - PubMed

Affiliation: Department of Anaesthesiology, The University of Hong Kong, Pokfulam, Hong Kong.

ABSTRACT
Ischemia and inflammation may be pathophysiological mechanisms of complex regional pain syndrome (CRPS). Ketamine has proposed anti-inflammatory effects and has been used for treating CRPS. This study aimed to evaluate anti-inflammatory and analgesic effects of ketamine after ischaemia-reperfusion injury in a chronic postischaemia pain (CPIP) model of CRPS-I. Using this model, ischemia was induced in the hindlimbs of male Sprague-Dawley rats. Ketamine, methylprednisolone, or saline was administered immediately after reperfusion. Physical effects, (oedema, temperature, and mechanical and cold allodynia) in the bilateral hindpaws, were assessed from 48 hours after reperfusion. Fewer (56%) rats in the ketamine group developed CPIP at the 48th hour after reperfusion (nonsignificant). Ketamine treated rats showed a significantly lower temperature in the ischaemic hindpaw compared to saline (P < 0.01) and methylprednisolone (P < 0.05) groups. Mechanical and cold allodynia were significantly lower in the ischaemic side in the ketamine group (P < 0.05). Proinflammatory cytokines TNF-α and IL-2 were significantly lower at the 48th hour after reperfusion in ketamine and methylprednisolone groups, compared to saline (all P < 0.05). In conclusion, immediate administration of ketamine after an ischaemia-reperfusion injury can alleviate pain and inflammation in the CPIP model and has potential to treat postischaemic pain.

No MeSH data available.


Related in: MedlinePlus

Hindpaw temperatures of KE, MP, and NS groups on the ipsilateral (a) and contralateral side (b) from baseline before ischaemia until the first 7 days after reperfusion. The temperature in group KE was lower in the ipsilateral side, compared with MP (P < 0.05) and NS (P < 0.01) groups. However, the difference was only obvious up to the 6th hour after reperfusion. Group KE also had decreased hindpaw temperature on the contralateral side during the same period, compared with group NS (P < 0.05); *P < 0.05 and **P < 0.01.
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fig1: Hindpaw temperatures of KE, MP, and NS groups on the ipsilateral (a) and contralateral side (b) from baseline before ischaemia until the first 7 days after reperfusion. The temperature in group KE was lower in the ipsilateral side, compared with MP (P < 0.05) and NS (P < 0.01) groups. However, the difference was only obvious up to the 6th hour after reperfusion. Group KE also had decreased hindpaw temperature on the contralateral side during the same period, compared with group NS (P < 0.05); *P < 0.05 and **P < 0.01.

Mentions: Our thermography study showed that the temperature on the ipsilateral side hindpaws of group KE rats was lower than in the NS and MP group rats (P < 0.01 and P < 0.05, resp., Figure 1(a)). Ketamine also attenuated the rise in the hindpaw temperature on the contralateral side during the same period compared with group NS (P < 0.05, Figure 1(b)). Although there was a clear difference, it was only obvious up to the sixth hour after reperfusion. We also monitored the hindpaw thickness but no obvious difference was found between all three treatment groups in the ipsilateral and contralateral sides (Figures 2(a) and 2(b)).


Preventive Treatment with Ketamine Attenuates the Ischaemia-Reperfusion Response in a Chronic Postischaemia Pain Model.

Liman S, Cheung CW, Wong KL, Tai W, Qiu Q, Ng KF, Choi SW, Irwin M - Oxid Med Cell Longev (2015)

Hindpaw temperatures of KE, MP, and NS groups on the ipsilateral (a) and contralateral side (b) from baseline before ischaemia until the first 7 days after reperfusion. The temperature in group KE was lower in the ipsilateral side, compared with MP (P < 0.05) and NS (P < 0.01) groups. However, the difference was only obvious up to the 6th hour after reperfusion. Group KE also had decreased hindpaw temperature on the contralateral side during the same period, compared with group NS (P < 0.05); *P < 0.05 and **P < 0.01.
© Copyright Policy - open-access
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC4487903&req=5

fig1: Hindpaw temperatures of KE, MP, and NS groups on the ipsilateral (a) and contralateral side (b) from baseline before ischaemia until the first 7 days after reperfusion. The temperature in group KE was lower in the ipsilateral side, compared with MP (P < 0.05) and NS (P < 0.01) groups. However, the difference was only obvious up to the 6th hour after reperfusion. Group KE also had decreased hindpaw temperature on the contralateral side during the same period, compared with group NS (P < 0.05); *P < 0.05 and **P < 0.01.
Mentions: Our thermography study showed that the temperature on the ipsilateral side hindpaws of group KE rats was lower than in the NS and MP group rats (P < 0.01 and P < 0.05, resp., Figure 1(a)). Ketamine also attenuated the rise in the hindpaw temperature on the contralateral side during the same period compared with group NS (P < 0.05, Figure 1(b)). Although there was a clear difference, it was only obvious up to the sixth hour after reperfusion. We also monitored the hindpaw thickness but no obvious difference was found between all three treatment groups in the ipsilateral and contralateral sides (Figures 2(a) and 2(b)).

Bottom Line: Ketamine treated rats showed a significantly lower temperature in the ischaemic hindpaw compared to saline (P < 0.01) and methylprednisolone (P < 0.05) groups.Mechanical and cold allodynia were significantly lower in the ischaemic side in the ketamine group (P < 0.05).In conclusion, immediate administration of ketamine after an ischaemia-reperfusion injury can alleviate pain and inflammation in the CPIP model and has potential to treat postischaemic pain.

View Article: PubMed Central - PubMed

Affiliation: Department of Anaesthesiology, The University of Hong Kong, Pokfulam, Hong Kong.

ABSTRACT
Ischemia and inflammation may be pathophysiological mechanisms of complex regional pain syndrome (CRPS). Ketamine has proposed anti-inflammatory effects and has been used for treating CRPS. This study aimed to evaluate anti-inflammatory and analgesic effects of ketamine after ischaemia-reperfusion injury in a chronic postischaemia pain (CPIP) model of CRPS-I. Using this model, ischemia was induced in the hindlimbs of male Sprague-Dawley rats. Ketamine, methylprednisolone, or saline was administered immediately after reperfusion. Physical effects, (oedema, temperature, and mechanical and cold allodynia) in the bilateral hindpaws, were assessed from 48 hours after reperfusion. Fewer (56%) rats in the ketamine group developed CPIP at the 48th hour after reperfusion (nonsignificant). Ketamine treated rats showed a significantly lower temperature in the ischaemic hindpaw compared to saline (P < 0.01) and methylprednisolone (P < 0.05) groups. Mechanical and cold allodynia were significantly lower in the ischaemic side in the ketamine group (P < 0.05). Proinflammatory cytokines TNF-α and IL-2 were significantly lower at the 48th hour after reperfusion in ketamine and methylprednisolone groups, compared to saline (all P < 0.05). In conclusion, immediate administration of ketamine after an ischaemia-reperfusion injury can alleviate pain and inflammation in the CPIP model and has potential to treat postischaemic pain.

No MeSH data available.


Related in: MedlinePlus