Involvement of serotonin in stress-induced alterations of malignant tumor growth

Effect of chronic and acute foot shock: stress on tumor growth pattern and its concomitant influence on central 5-HT concentration has been evaluated in experimental mice bearing Sarcoma-180. while exposure to chronic stress caused appreciable decrease in total tumor cell count with a parallel decre ase in brain 5-HT levels, acute stress resulted in significant increase in the total tumor cell count and levels of central 5-HT and its metabolite 5- HIAA. Treatment with 5-HT re-uptake blocker, imipramine,(10mg/kg body wt./d ay) caused inhibition of tumor growth in the treated groups compared to unt reated acute-stressed tumor bearers. The results point to the involvement o f 5-HT in mediating stress induced tumor growth alteration.