Figure 1.

Effects of photoperiod on the expression of Dio2 and Dio3 in the ependymal cell layer lining the infundibular recess of the third ventricle. C3H mice of wild type were kept either under short-day (SD, black circles) or under long-day (LD, white circles) conditions for 2 weeks. Representative autoradiograms are shown above the graphs (scale bars, 1 mm). Data at ZT2 are double plotted. The black and white bars below the graphs indicate the light/dark period. Asterisks indicate significant differences between mice kept under SD and LD at each time point (t test, *p < 0.05; n = 3–4). Error bars indicate SEM.