Effect of naloxone on luteinizing hormone secretion in premenstrual syndrome.

OBJECTIVES

To investigate the theory of brain opioid activity disregulation in premenstrual syndrome (PMS) and to discover the changes of central beta-endorphin activity during the menstrual cycle in PMS patients.

DESIGN

Prospective study.

SETTING

University-based PMS clinic.

PATIENTS

All the patients and controls were between 20 and 45 years of age, with regular menses for at least six previous cycles. All the patients demonstrated at least 30% score increase in designated symptoms on the Visual Linear Analog Scale during the luteal phase compared with the follicular phase. In contrast, the score changes in the controls were < 30%.

INTERVENTIONS

All subjects underwent LH-releasing hormone (LH-RH) stimulation test on days 2 to 3 of the cycle. Five naloxone infusions were administered on days 7 to 8 and 10 to 11, 1 day, 3 to 4 days, and 12 to 13 days after the LH surge as detected by the ovulation prediction kit.

MAIN OUTCOME MEASURES

Luteinizing Hormone levels were recorded for 1 hour, followed by naloxone infusion at 2 mg/h for 4 hours. Blood samples were collected for LH tests every 15 minutes for 1 hour before, during, and for 1 hour after the infusion.

RESULTS

All subjects had similar LH response to LH-RH. The integrated area of LH response to naloxone as expressed by percentage of the baseline on each of the 5 days did not show significant differences between the patients and the controls.

CONCLUSIONS

The central beta-endorphin changes, if any, in PMS patients could not be demonstrated in our study.