Effects of intrathecal anandamide on somatosensory evoked responses in rats.
Anandamide, endogenous ligand of cannabinoid receptors produces similar effects of cannabinoids via CB1 receptors in the central nervous system. Its effect on ascending pathways of somatosensory conduction and somatosensory cortex is not known. The aim of this study was to determine the effects of anandamide on somatosensory evoked potentials (SEP). In this study, 24 Wistar male rats were used. The rats were divided into 4 groups. At the beginning, sciatic nerve stimulated scalp SEP traces were obtained from all of the rats. Later, 0.02 cm(3) anhydrous ethanol, 100 microg/kg, 200 microg/kg and 400 microg/kg anandamide dissolved in anhydrous ethanol were injected intrathecally to the first (control), second, third and fourth groups, respectively. Five minutes later, second SEP traces were started. In every SEP trace, two negative waves (N1, N2) following positive deflections were obtained. The latency and amplitudes of these waves assessed were compared in each group. In control and second groups, the parameters of these waves before and after the injections were not significantly different. However, in the third and fourth groups, latencies of N1 and N2 after injections were found significantly longer. This effect was dose dependent. In any of the groups, no significant changes were detected in the amplitudes after injections. In conclusion, anandamide, when injected intrathecally in pharmacological doses caused an induction of moderate conduction delay in SEP systems.
Bir
Levent Sinan
LS
Department of Neurology, Pamukkale Universitesi Tip Fakültesi Hastanesi Nöroloji AD. B-105, 20070 Kinikli-Denizli, Turkey. sbir@pamukkale.edu.tr
Ercan
Sevim
S
D000818:Animals; D001095:Arachidonic Acids / Q000494:pharmacology*; D063385:Cannabinoid Receptor Modulators / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D004569:Electroencephalography; D063388:Endocannabinoids; D005073:Evoked Potentials, Somatosensory / Q000187:drug effects*; D008297:Male; D053284:Polyunsaturated Alkamides; D051381:Rats; D017208:Rats, Wistar; D011930:Reaction Time / Q000187:drug effects; D013003:Somatosensory Cortex / Q000187:drug effects*; D018709:Statistics, Nonparametric
D001095:Arachidonic Acids; D063385:Cannabinoid Receptor Modulators; D063388:Endocannabinoids; D053284:Polyunsaturated Alkamides; C078814:anandamide