A specific profile of luteal phase progesterone is associated with the development of premenstrual symptoms.

There is a consensus that the development of premenstrual dysphoric states is related to cyclical change in gonadal hormone secretion during the menstrual cycle. However, results from studies seeking to link symptom severity to luteal phase progesterone concentration have been equivocal. In the present study we evaluated not only the absolute concentrations of progesterone but also the kinetics of the change in progesterone concentration in relation to development of premenstrual symptoms during the last 10days of the luteal phase in a population of 46 healthy young adult Brazilian women aged 18-39 years, mean 26.5±6.7years. In participants who developed symptoms of premenstrual distress, daily saliva progesterone concentration remained stable during most of the mid-late luteal phase, before declining sharply during the last 3days prior to onset of menstruation. In contrast, progesterone concentration in asymptomatic women underwent a gradual decline over the last 8days prior to menstruation. Neither maximum nor minimum concentrations of progesterone in the two groups were related to the appearance or severity of premenstrual symptoms. We propose that individual differences in the kinetics of progesterone secretion and/or metabolism may confer differential susceptibility to the development of premenstrual syndrome.

Effects of diazepam on BOLD activation during the processing of aversive faces.

This study aimed to measure, using fMRI, the effect of diazepam on the haemodynamic response to emotional faces. Twelve healthy male volunteers (mean age = 24.83 ± 3.16 years), were evaluated in a randomized, balanced-order, double-blind, placebo-controlled crossover design. Diazepam (10 mg) or placebo was given 1 h before the neuroimaging acquisition. In a blocked design covert face emotional task, subjects were presented with neutral (A) and aversive (B) (angry or fearful) faces. Participants were also submitted to an explicit emotional face recognition task, and subjective anxiety was evaluated throughout the procedures. Diazepam attenuated the activation of right amygdala and right orbitofrontal cortex and enhanced the activation of right anterior cingulate cortex (ACC) to fearful faces. In contrast, diazepam enhanced the activation of posterior left insula and attenuated the activation of bilateral ACC to angry faces. In the behavioural task, diazepam impaired the recognition of fear in female faces. Under the action of diazepam, volunteers were less anxious at the end of the experimental session. These results suggest that benzodiazepines can differentially modulate brain activation to aversive stimuli, depending on the stimulus features and indicate a role of amygdala and insula in the anxiolytic action of benzodiazepines.