HORMONAL AND SUBJECTIVE RESPONSES TO INTRAVENOUS M-CHLOROPHENYLPIPERAZINE IN WOMEN WITH SEASONAL AFFECTIVE-DISORDER

Background: There is emerging evidence of serotonergic dysfunction in patients with seasonal affective disorder (SAD). We examined central s erotonergic function in female patients with SAD (fall-winter pattern) by means of neuroendocrine and subjective responses to the postsynapt ic serotonin receptor agonist m-chlorophenylpiperazine. Methods: Using a double-blind, randomized, placebo-controlled design, we assessed ne uroendocrine and subjective responses to m-chlorophenylpiperazine. (0. 1 mg/kg intravenously) and placebo in 14 unmedicated female patients w ith SAD in the depressed state and 15 female normal controls. All test ing was done in the fall-winter months and during the follicular phase of the menstrual cycle. Plasma prolactin and cortisol levels were use d as neuroendocrine measures, while subjective responses were assessed by means of visual analog scales of 10 mood states. Results: On the b asis of net responses to m-chlorophenylpiperazine. (placebo effects su btracted from drug effects), patients with SAD exhibited blunted prola ctin responses and less sadness than normal controls in response to th e drug. When order of presentation of drug and placebo was taken into consideration, altered ''calm'' and ''high'' responses were also found in the patient group. Conclusion: Evidence of dysfunction at or downs tream to central serotonergic receptors in Female patients with SAD co nfirms and extends findings from previous research.