Here, we also observed reduced urinary levels of the endogenous parent estrogens (E2 and E1) in COC users (Table 1)
Tanaka Y, Takeuchi T, Yamanaka H, Nanki T, Umehara H, Yasuda N, Tago F, Kitahara Y, Kawakubo M, Torii K
Cognitive reserve in ageing and Alzheimer's disease
Van de Peer, Y., Mizrachi, E.& Marchal, K
Endogenous glucocorticoid secretion follows a conserved circadian pattern across species, with diurnal organisms (e.g., humans) showing peak concentrations during active phases (morning) and nocturnal species (e.g., rodents) displaying maximal levels during their active period (evening) (126).In humans, peak circadian cortisol secretion (approximately 06:0010:00h) (127) temporally coincides with maximal expression of tight junction proteins (occludin, claudin-5), and optimal BBB integrity