The study investigates the protective effect of Acorus calamus L. (AC) in
vincristine-induced
painful neuropathy.
Vincristine (75μg/kg, i.p. for 10 consecutive days) was administered to induce
painful neuropathy in rats. Various tests were performed to assess the degree of
painful neuropathy at different days i.e., 0, 1, 7, 14, and 21st day. Sciatic nerve TNF-α,
superoxide anion generation, total
calcium, and
myeloperoxidase activity level were also estimated after 21st day of study. Hydro-alcoholic extract of AC (HAE-AC, 100 and 200mg/kg, p.o.) and
pregabalin (10mg/kg, p.o.) were administered for 14 consecutive days.
Vincristine significantly induced
neuropathic pain manifested in the terms of
thermal hyperalgesia and
allodynia (increase in hind paw licking, lifting or jumping from hot plate);
mechanical hyperalgesia (increase in left hind paw lifting duration in pin-prick test) and
allodynia (left hind paw withdrawal reflexes to non-noxious stimuli in Von Frey test); and sciatic functional index (analysis of footprints of the feet) along with rise in the levels of various biochemicals. HAE-AC attenuated
vincristine induced behavioral, and biochemical changes comparable to that of
pregabalin (positive control). HAE-AC attenuated
vincristine induced
painful neuropathy, which may be attributed to its multiple effects including anti-oxidative, anti-inflammatory, and
calcium inhibitory actions.