Intrathecal administration of clonidine or yohimbine decreases the nociceptive behavior caused by formalin injection in the marsh terrapin (Pelomedusa subrufa)

Brain and Behavior

Christopher M. Makau²  Philemon K. Towett²  Klas S. P. Abelson¹ 

[1] Department of Experimental Medicine, University of Copenhagen, Faculty of Health Sciences, Copenhagen N, Denmark;Department of Veterinary Anatomy and Physiology, University of Nairobi, Nairobi, Kenya

关键词: Antinociception;    nociception;    testudines;    α2‐adrenergic receptors;   

DOI  :  10.1002/brb3.287

来源: Wiley

【 摘 要 】

Abstract

Background

The role of noradrenergic system in the control of nociception is documented in some vertebrate animals. However, there are no data showing the role of this system on nociception in the marsh terrapins.

Methodology

In this study, the antinociceptive action of intrathecal administration of the α₂-adrenoreceptor agonist clonidine and α₂-adrenoreceptor antagonist yohimbine was evaluated in the African marsh terrapin using the formalin test. The interaction of clonidine and yohimbine was also evaluated.

Results

Intrathecal administration of clonidine (37.5 or 65 μg/kg) caused a significant reduction in the mean time spent in pain-related behavior. Yohimbine, at a dose of 25 μg/kg, significantly blocked the effect of clonidine (65 μg/kg). However, administration of yohimbine (40 or 53 μg/kg) caused a significant reduction in the mean time spent in pain-related behavior. Intrathecal administration of yohimbine (53 μg/kg) followed immediately by intrathecal injection of the serotonergic methysergide maleate (20 μg/kg) resulted in a significant reversal of the antinociceptive effect of yohimbine.

Conclusion

The present study documented the intrathecal administration of drugs in the marsh terrapin, a technique that can be applied in future studies on these animals. The data also suggest the involvement of both α₂-adrenoreceptors and 5HT receptors in the modulation of nociception in testudines.

【 授权许可】

CC BY   
© 2014 The Authors. Brain and Behavior published by Wiley Periodicals, Inc.

Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.