Fig. 2 eNOS expression in homogenates of hypothalamus (a), mesencephalon (b) and medulla (c) of rats injected with glyceryl trinitrate (GTN) or vehicle (CT). The histograms illustrate the densitometric analysis representing expression levels of eNOS (130KDa) as ratio vs β-actin (39 kDa). The latter protein was used as a housekeeping protein on the same membrane previously incubated with eNOS. In the right of each panel are illustrated representative western blots of eNOS protein. eNOS expression was evaluated after 4 h of GTN or vehicle injection. Data are expressed as mean ± SD. Mann Whitney test, *p < 0.05 vs vehicle (CT)