An assessment of crosstalk between serotonin and dopamine systems after escitalopram treatment using LC-MS technique with ion-trap analyser

The present work was aimed at developing and validating a highly sensitive analytical method to estimate the levels of monoamines from mice brain and to apply the developed method to assess the effect of escitalopram treatment on the levels of serotonin, dopamine and noradrenaline in the mouse brain. Liquid chromatography-mass spectroscopy was optimized to achieve separation of selected neurotransmitters. Method validation was performed as per the ICH guidelines. Extraction of the neurotransmitters from mice brain tissue was optimized to achieve highest recovery. In vivo study involved behavioural profile assessment after 7 d pre-treatment with escitalopram and correlating the results with monoamines levels in their brain homogenate. Behavioural profiles showed a significant (p<0.05) change in all tested parameters. These values were in agreement with the significant rise in serotonin levels (p<0.05) seen on escitalopram treatment compared to vehicle control. Along with the elevation in serotonin levels, a significant increase in levels of dopamine and a mild increase in noradrenaline levels was observed due to the possible crosstalk between the neurotransmission pathways. Liquid chromatography-mass spectroscopy method was developed and validated for estimation of brain neurotransmitters which revealed a crosstalk resulting in the elevation in levels of various monoamines after escitalopram treatment.