The present study was designed to investigate the analgesic potential of 7-
hydroxy-4-methylcoumarin (HMC) in acrylamide induced neuropathic pain in rats.
Acrylamide (30 mg/kg, i.p.; once in three days, for 24 consecutive days) was
administered for inducing neuropathic pain. The acrylamide induced nociceptive pain
sensation, i.e., acetone drop, plantar, hot plate, Von Frey Hair and tail immersion tests
have been assessed at different time intervals, i.e., 0, 6, 12, 18 and 24th day.
Furthermore, the biochemical estimation, i.e., thiobarbituric acid reactive substances
(TBARS), reduced glutathione (GSH), total calcium, cytochrome c oxidase activity and
ATP content levels were estimated from the sciatic nerve tissue sample on 24th day. The
HMC (10 and 20 mg/kg, p.o.) and cyclosporin A (CsA, 50 μM/kg; p.o.) was
administered for 24 consecutive days, one hour before each injection of acrylamide.
The treatment of acrylamide resulted in significant (P < 0.05) changes of behavioral
and biochemical changes. Pretreatment of HMC ameliorate the acrylamide induced
changes of behavioral and biochemical parameters in a dose dependent manner. These
results are similar to that of CsA treated group. Based on these findings, it may
conclude that, HMC possesses the potential ameliorative effect against acrylamide
induced neuropathic pain, it may be because of its therapeutic potential of anti-oxidant,
anti-lipidperoxidative, calcium ion regulatory and mitochondrial permeability transition
pore inhibitory action.
Keywords: 7-hydroxy-4-methylcoumarin, Acrylamide, Adenosine triphosphate,
Allodynia, Calcium, Cyclosporin A, Cytochrome c oxidase, Electron transport
chain, Hyperalgesia, Mitochondrial dysfunction.
