Inhibitory effect of ascorbic acid on development of dependency to heroin in rats

Introduction: There are several line of evidences that dopamine release from dopaminergic neurons of VTA increases during heroin administration and ascorbic acid (AA) regulates this dopamine release. The main object of present study was, to determine the effect of 3 different doses of AA on dependence to heroin. Materials and Methods: Male wistar rats were implanted with silastic catheters into the right jugular vein. After recovery animals are studied in 3 groups (control, heroin and AA) through IV self administration (SA) method by two lever (active and passive) for 2h every day until 15 days. During the first 5 days animals were hungry since 12h before SA, While during the remaining 10 days were not. The latter group (AA) composed of 3 subgroups (a, b, c) that got different doses(100, 300, 700 mg/kg.IP) of AA 30 minutes before SA, respectively. Results: AA injection decreased active lever pressing and the effects of doses applied in this study were almost the same. Number of lever pressing in all groups was as follows (mean ± SEM): Lever Group salin Heroin Ascorbate a Ascorbate b Ascorbate c Passive 1.97 ± 0.18 6.48 ± 0.39 6.03 ± 0.34 5.65 ± 0.35 5.11± 0.31 Active 11.13± 0.62 41.48± 1.82 25.68± 1.07 25.24±1 .05 23.89± 0.94 Conclusion: Injection of AA prevented the reinforcing effect of heroin and developing dependence to it. There was no significant difference between different doses of AA in this issue.