ABSTRACT
Background: Anxiety is a widespread disorder that approximately 18% of the population experience at some stage in their lives. Pain is a common stimulus that induces anxiety in both animals and human beings. Combination of drugs with good anti-anxiety and analgesic effect can be used for the treatment of chronic pain induced anxiety, post-operative, and procedure-related pain-induced anxiety. Aims and Objectives: The study was conducted to evaluate the anxiolytic activity of combination of gabapentin with tramadol, pregabalin with tramadol compared to standard fluoxetine, in elevated plus maze (EPM) and light-dark arena (LDA) models of anxiety in Wistar albino rats. Materials and Methods: Twenty-four male or female albino Wistar rats from Central Animal House, MRMC, Kalaburagi, were utilized. Fluoxetine 10 mg/kg, gabapentin 30 mg/kg, tramadol 30 mg/kg, and pregabalin 30 mg/kg were used. Eddy’s hot plate method used for inducing anxiety. EPM and LDA models were used to study the effect of drugs in reducing the pain and anxiety. Results: The present study showed that the exposure to hot plate induces pain, creates anxiety, and reduces locomotor and explorative activity among the rats when exposed to hot plate. There was reduction in anxiety after drug administration, in fluoxetine and gabapentin with tramadol groups with >75% increase in entry into the light chamber or open arm at least once or more during the time period of 5 min when compared to hot plate post-exposure readings. Whereas in pregabalin and tramadol group, it was observed that 25% increase in entry of rats into open arm at least once during the time period of 5 min and 25% decrease in entry of rats into light chamber as compared to those rats after exposure to hot plate. Conclusion: Our study has demonstrated that tramadol, pregabalin, and gabapentin have got analgesic as well as anti-anxiety effects in rats when given in combination. All these experimental data, together with the previous experimental studies and the results reported in this work, suggest that combination of these drugs could be more effective in treating anxiety-related disorders such as chronic pain, pain-induced anxiety, post-operative, and procedure-related pain-induced anxiety with minimal side effects. Further dose ranging studies and models might be necessary to better understand the effects of these drugs in combination.
ABSTRACT
Background: Pain is a common stimulus that induces anxiety in both Animals and human beings. Aim and Objective: We have undertaken this study to evaluate the induction of anxiety in Wistar rats using hot plate method. Materials and Methods: 24 Wistar rats of either gender were used. Elevated plus maze (EPM) and light and dark arena (LDA) were used to evaluate the anxiety and hot plate analgesiometer was used to induce anxiety. After baseline reading from EPM and LDA, the Wistar rats were exposed to the hot plate and then evaluated for the induction of the anxiety behavior. Results: After exposing to the hot plate, the ratio of time spent in the open arms to the time spent on the closed arms was decreased from 0.027 to 0.010 and also the ratio of time spent on the light chamber to the time spent on the dark chamber was decreased from 0.093 to 0.012. Hot plate method has shown statistical significant induction of anxiety as evaluated by EPM and also LDA. Conclusion: Hot plate method is a good intervention to induce anxiety in Wistar rats. Instead of injecting drugs that causes anxiety to explore the anxiolytic effects of the drugs the hot plate analgesiometer method is a good alternative.