Spinal nerve ligation model

It has been demonstrated that neuropathic pain is opioid resistant and, indeed, neither systemic nor i.t. administration of opioids reduced effectively neuropathic pain in rats (Bian et al., 1995 Lee et al., 1995 Mao et al., 1995 Ossipov et al., 1995). It seems worth to note that s.c. administration of (—) linalool attenuates mechanical allodynia in spinal nerve ligation model of neuropathic pain in mice (Levato et al., 2006). 

AM1241 (360) exhibited high affinity and selectivity for CB2 [it (CBi) = 280 nM, (CB2) = 3.4 nM]. (360) Dose dependently inhibited experimental neuropathic pain in a spinal nerve ligation-induced tactile and thermal hypersensitivity model [224]. Other indole derivatives bearing sulfonamide moieties on the side chain, such as compound (361), were disclosed [225]. Though 67 derivatives including pyridyl and other heteroaromatics instead of the indole core were listed, no specific biological data were shown. 

Kim, S. H. and Chung, J. M. An experimental model for peripheral neuropathy produced by segmental spinal nerve ligation in the rat, Pain 1992, 50, 355-363. 

Compounds with moderate p-affinities are very potent in a variety of pain models in mice and rats. In addition to antinociceptive efficacy in models of acute pain (tail flick, writhing) these compounds inhibit acute and persistent inflammatory pain (Randall Selitto, formalin test). Furthermore, they show strong inhibition of acute visceral pain (colorectal distension) and of tactile and cold allodynia in models of neuropathic pain (spinal nerve ligation (Chung), chronic constriction injury (Bennett)). The data suggest these compounds to be potential candidates for the management of clinical pain indications. Somatic and visceral pain with and without inflammatory conditions as well as neuropathic pain might be addressed with this approach. 

SNX-111, when given alone, is active in the Chung model (spinal nerve ligation), tactile allodynia test (hindpaw UV burn) and paw pressure test. In the hot plate assay there is only a small but significant effect of about 20% increase in response latency (Table 4, Malmberg and Yaksh, 1994). 

Chung model (spinal nerve ligation) SNX-111 0. 03, 0.1 and 0.3 pg 1. t. Dose-dependent blockade of mechan. allodynia in neuropathy rats Bowersox et al. (1998)... 

Linalool is a natural compound with anti-inflammatory and antinociceptive properties. The antinociceptive action of Iinalool has been reported in several models of inflammatory pain. However, its effects in neuropathic pain have not been investigated. Here, we used the spinal nerve ligation (SNL) model of... 

While the antinociceptive effect exerted by linalool has been extensively investigated in inflammatory pain, no studies exist on the effects of linalool in models of neuropathic pain. To this aim, we used the spinal nerve ligation (SNL) model of neuropathic pain (Kim and Chung, 1992) and studied the effects of acute and chronic administration of (—)-linalool on mechanical and thermal hypersensitivity induced by nerve injury in mice. 

Gold There does seem to be some disagreement on this point. The spinal nerve ligation (SNL) model is a model of nerve injury that has been used to determine whether nerve injury results in changes in Na channel expression in uninjured nerves. The sciatic nerve is comprised of axons arising from L4, L5 and L6 dorsal root ganglia. If you cut one or two of the spinal nerves, say L5 and L6, before they join the common nerve, the result is a pain syndrome with symptoms similar to... 

In mice, ABT-594 produces antinociceptive effects in both the hot-plate test and the abdominal constriction assay. In rats, similar results are obtained in the thermal paw withdrawal test and the formalin test. The efficacy of ABT-594 in these tests is similar to or better than that of morphine, and ABT-594 is at least 30 times more potent than morphine. In addition, ABT-594 is effective in the spinal nerve ligation (Chung) model of neuropathic pain. In all of these models, ABT-594 shows a rapid onset of action and activity after oral administration. 

The mechanism by which gabapentin exerts its analgesic action is unknown. It has been shown in animal models to prevent allodynia (pain-related behavior in response to a normally innocuous stimulus) and hyperalgesia (exaggerated response to painful stimuli). Particularly, gabapentin has been shown to attenuate pain-related responses in several animal models of neuropathic pain (diabetes, spinal nerve ligation, spinal cord injury, acute herpes zoster infection) and also decreases pain-related responses after peripheral inflammation. However, gabapentin did not alter immediate pain-related behaviors in animal models. 

Chung model of neuropathic pain Nerve injury in rats is induced by a tight ligation of the root of the spinal nerve at L5-L6. Animals show hyperalgesia and allodynia similar to the Bennet model. Tactile allodynia, measured with von Frey hairs, is the most reliable parameter of pain intensity in this model (Kim and Chung, Pain 1992, 50, 355-363). 

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