Objective: To study the pre and post synaptic 5-HT1A receptor dependent responses in rats following Rice bran oil (RBO) treatment.
Methods: Male albino Wistar rats were first categorized into two groups. Standard rodent food was given to all groups. RBO-treated rats were given RBO (0.2 ml/day) daily for six weeks. After six weeks, the rats were subdivided into further two groups. Rats of first subgroup were injected with saline and second group with 8-hydroxy-2-(di-npropylamino) tetralin (8-OH-DPAT) at a dose of 0.25 mg/kg. 8-OH-DPAT-induced behavioral activity was monitored just after 5 minutes of injections till 25 minutes. One hour after saline or drug injections, animals were sacrificed. Plasma and brain samples were then stored for the estimation of cholesterol, glucose and corticosterone in plasma and concentrations of serotonin in brain.
Results: Intensity of serotonin syndrome produced by 8-OHDPAT and the effects of the drug on plasma glucose and corticosterone were greater in RBO treated than control rats suggesting that the treatment decreases postsynaptic 5- HT1A receptor dependent responses. Drug-induced decreases of brain 5-HT metabolism, a measure of presynaptic 5-HT1A receptor dependent response were also attenuated in RBO treated rats.
Conclusion: Down regulation of 5-HT1A autoreceptor receptor mediated feedback control over 5-HT synthesis and release is possibly played a role to have opposed the depression like effects by RBO.
Mehdi BJ, Haleem DJ