However, splitting the 30 mg/kg doses into several injections resulted in analgesia without undesirable side effects. We have used this dosing schedule in a mouse model of IoN-CCI and found it to be successful in reversing both von Frey hair and air puff–induced allodynia (Krzyzanowska et al. 2011). Morphine generally has a poor efficacy in TN patients, a result also observed in rats (Idanpaan-Heikkila and Guilbaud 1999). However, a combination of Inhibitors,research,lifescience,medical morphine and the NMDA receptor antagonist HA966, which by itself produced no analgesia, has been shown
to induce a profound morphine dose-dependent antinociception at nonsedative concentrations (Christensen et al. 1999). These findings have
been contradicted by other reports (Deseure et al. 2002) in which a decrease in hyper-responsiveness following treatment with morphine alone was indeed observed, a difference which the authors Inhibitors,research,lifescience,medical argue may lie in the method Inhibitors,research,lifescience,medical of behavioral testing. More recently, Le and colleagues (2010) have found both i.p. and intracisternal morphine to relieve mechanical allodynia following air-puff stimulation in rats with agar-compressed trigeminal ganglia. The drug studies in rodents have demonstrated that the inflammatory and neuropathic orofacial models can Inhibitors,research,lifescience,medical in some ways be representative of disorders such as TMD and TN and could be used to test new potential treatments.
The development of behavioral protocols in mice additionally allows for the study of various genes involved in orofacial pain states with the aid of transgenics. To date, numerous studies have used experimentally induced orofacial inflammation or neuropathy to demonstrate the analgesic properties of a number of novel Inhibitors,research,lifescience,medical compounds: the 5HT1A receptor agonist “type”:”entrez-nucleotide”,”attrs”:”text”:”F13640″,”term_id”:”747767″,”term_text”:”F13640″F13640 (Deseure et al. 2002), mitogen-activated protein kinase inhibitors Org 27569 PD98059 and SB203580 (Lim et al. 2007), phospholipase A2 inhibitors (Yeo et al. 2004) – to name but a few. Microtubule Associated inhibitor Conclusion It must be taken into account that none of the models described in this review exactly mirror human conditions. For example, human chronic inflammatory pain rarely arises from a peripheral injection of an irritant agent. Also, it is unlikely that clinical cases are caused by a compression of a peripheral branch of the trigeminal nerve such as the IoN or the mental nerve and no animal models exists mimicking human trigeminal root compression by vascular loops. In addition, it is difficult to design animal models for some more complex disorders that are not yet fully understood, such as the burning mouth syndrome.