Modulation of the suppressive effect of corticosterone on adult rat hippocampal cell proliferation by paroxetine

The literature has shown that cognitive and emotional changes may occur after chronic treatment with glucocorticoids. This might be caused by the suppressive effect of glucocorticoids on hippocampal neurogenesis and cell proliferation. Paroxetine, a selective serotonin reuptake transporter, is a commonly used antidepressant for alleviation of signs and symptoms of clinical depression. It was discovered to promote hippocampal neurogenesis in the past few years and we wanted to investigate its interaction with glucocorticoid in this study. Adult rats were given vehicle, corticosterone, paroxetine, or both corticosterone and paroxetine for 14 d. Cell proliferation in the dentate gyrus was quantified using 5-bromo-2-deoxyuridine (BrdU) immunohistochemistry. The corticosterone treatment suppressed while paroxetine treatment increased hippocampal cell proliferation. More importantly, paroxetine treatment could reverse the suppressive effect of corticosterone on hippocampal cell proliferation. This may have clinic application in preventing hippocampal damage after glucocorticoid treatment.