Fig. 1. Day/night variation in the retinal Drd4 expression in the Sprague-Dawley rat.
X-ray images of sagittal sections, hybridized for the Drd4-receptor, of rat eyeballs from a control rat (A and C) and from a rat (B and D), in which the superior cervical ganglia have been removed bilaterally (SCGx) ten days before sacrifice. Note the high nighttime expression, which is unaffected by ganglionectomy. E: densitometric quantification of the signals showing mean ±SEM of 5 animals. dpm = disintegrations per minute. * = p<0.05, ** = p<0.01. Scale bar = 2 mm.