Effect Of Intravenous Propacetamol On Behavior And C-Fos Protein Expression Of Rat With Formalin Hurting

Objective To investigate the antinociceptive effect of Intravenous propacetamol on behavior and expression of c-Fos protein in the spinal cord of the formalin hurting.Methods Thirty healthy male adult SD rats(300-350 g)were randomized into 5 groups. In the normal saline control group (group NS), 100μl of normal saline was injected Intravenously, which was followed by a subcutaneous administration of 100μL of normal saline into the hind plantar skin of rats 10 min later. In the formalin control group(group F), 20μL of normal saline was injected Intravenously, and followed by intraplantar administration of 100μL of 5% formalin. respectively, and followed by rat intra-plantar administration of 100μL of 5% formalin. The graded pain behavior was observed per 5 min during one hour immediately after the intra-plantar injection. At the 2-hour time point, and then, the spinal cord was removed for analysis of c-Fos protein like immunoreactive neurons(FLIN)at the dorsal horn in the L4-L6segments.Results Almost no pain response was observed in group NS,The typical biphasic pain response was observed in theformalingroup.acutal reaction time of group BF were shorter than that in group F.T-ardy time of group FB were shorter than that in group F.c-fos protein expression of group NS and B were not vided,a plenty of FLIN were mainly disposited layer III III IVof group F. FLIN of group BF were reduced.in every layer,FLIN of group FB were fewer than that in group F.Conclusion Intravenous propacetamol can successfully inhibit nociceptive behavior and c-Fos expression in spinal dorsal horn of formalin test rats.this is relieve pain mechanism of propacetamol.