Neuropeptide levels in premenstrual syndrome.

To determine whether changes in circulating levels of neuropeptides are associated with symptoms of premenstrual syndrome (PMS), 20 women with the diagnosis of PMS and 20 asymptomatic subjects were studied. The premenstrual beta-endorphin levels were significantly lower in PMS patients (P = 0.0001). The decrease in beta-endorphin levels during the luteal phase, compared with the follicular phase, in PMS patients was also significant (P = 0.0002). Neurotensin, human pancreatic peptide, vasoactive intestinal polypeptide, gastrin, and bombesin-like immunoreactivity levels did not reveal significant changes between days 7 and 25 in patients with PMS.