Progesterone Might Be an Active Component of the Sleep-Wake Homeostatic Mechanism

Abstract Background: Using a randomized, double blind, placebo-controlled, crossover protocol, we have shown previously that progesterone may prevent sleep disturbances but has no action on undisturbed sleep. In study, 8 healthy postmenopausal women took daily at 2300 h for 3 wk capsule of either 300 mg or placebo. Sleep was polygraphically recorded during the last two nights and, second night, blood samples were collected 15-min intervals using an iv catheter,. During first normal under placebo and had effect. sampling procedure associated with marked disturbances, which considerably reduced progesterone: group level, mean ± SEM duration wake after onset (WASO) dropped from 152 37 min to 71 19 (P = 0.01), slow-wave (SWS) increased 53 6 79 10 0.04). Objective: To submit individual data in study new analyses designed further investigate possible mechanism(s) actions architecture. Results: Among subjects, relation could be evidenced between levels variables, progesterone-associated improvements absolute values corresponding variables By contrast, WASO SWS, significant positive correlations (Spearman test) responses (i.e. difference, night 2, value placebo) alterations caused by placebo, 1 2): WASO: rs 0.74, P 0.037, n 8; SWS: 0.86, 0.014, 7. (Pearson test yielded similar results: r 0.85, 0.008; 0.76, 0.047). Conclusions: Although they obviously need confirmed larger studies performed variety clinical conditions, present findings suggest architecture is specifically tailored restore normality rather than normality. Since SWS mainly regulated sleep-wake homeostatic mechanism relating pressure prior wakefulness, it tempting speculate might active component this mechanism.