CIRCADIAN VARIATIONS IN THE NUMBER OF ACTIVELY SECRETING SEBACEOUS FOLLICLES AND ANDROGEN CIRCADIAN-RHYTHMS

Sebum excretion has been shown to demonstrate a circadian rhythm using a gravimetric method (cigarette paper). With the newly introduced met hod of Sebutape, we confirmed this periodicity and showed that the ele vation in sebum excretion is correlated with an increase in the number of secreting follicles. We found, furthermore, that the number of sec reting follicles on the forehead showed a distinct and statistically s ignificant circadian rhythmicity, in contrast to those of the chest, w hich remained almost constant. The quantification in plasma levels of cortisol, melatonin, DELTA-4-androstenedione, dehydroepiandrosterone s ulphate, and free testosterone showed no correlation with sebum excret ion at either site. These observations suggest that local factors are involved in control of sebum secretion.