Effects of repeated maprotiline and fluoxetine treatment on gene expression of catecholamine synthesizing enzymes in adrenal medulla of unstressed and stressed rats

1 Repeated maprotiline (a noradrenaline reuptake inhibitor) and fluoxetine (a serotonin reuptake inhibitor) treatment on gene expression of catecholamine biosynthetic enzymes were examined in adrenal medulla of unstressed control and chronic unpredictable mild stressed rats.

2 Maprotiline did not change gene expression of catecholamine biosynthetic enzymes in control and stressed rats.

3 Fluoxetine increased gene expression of tyrosine hydroxylase (TH) and dopamine-β-hydroxylase (DBH), but did not phenylethanolamine N-methyltransferase in both unstressed and chronic unpredictable mild stressed animals.

4 In conclusion, we have demonstrated that repeated administration of fluoxetine enhanced gene transcription of TH and DBH and subsequently stimulates noradrenaline synthesis in adrenal medulla of control and stressed rats.