Abstract
Background: The paragigantocellularis nucleus (PGI) is a part of medullarypontine reticular formation which plays an important role in pain processing. Some investigations have shown that activation of PGI neurons causes inhibition of pain inputs received in the central nervous system. Objective: To determine the effects of unilateral electrolytic lesion of dorsal and lateral PGI nucleus on acute and chronic pain induced by formalin in rats. Methods: 30 NMRI male rats (200-250gr) in five groups (control, DPGI lesioned, LPGI lesioned and two sham lesioned groups) were used. Being anesthetized with ketamine hydrochloride (110mg/kg/ip), DPGI and LPGI subdivisions of rats’ brain were lesioned electrolyticaly under stereotaxic operation. Following the recovery of incision the rats’ acute and chronic pain score were evaluated by formalin test (50 l, 2.5%). Findings: Results showed that the lesion of dorsal-PGI affected neither acute nor chronic pain induced by formalin. Lesion of lateral-PGI did not affect acute pain, but increased chronic pain score significantly (P<0.02). Conclusion: It seems that dorsal-PGI neurons have no noticeable effect on pain score.
Keywords
Paragigantocellularis Nucleus Electrolytic lesion Formalin Test Pain Rat
Copyright
© 2024, Journal of Inflammatory Diseases. This open-access article is available under the Creative Commons Attribution-NonCommercial 4.0 (CC BY-NC 4.0) International License (https://creativecommons.org/licenses/by-nc/4.0/), which allows for the copying and redistribution of the material only for noncommercial purposes, provided that the original work is properly cited.