J.R.V. Graça, G.M. Macedo, R.C. Palheta Jr., F. de A.A. Gondim, R.O. Nogueira, J.M. Correia, F.H. Rola, R.B. Oliveira, M.A.N. Souza and A.A. Santos. Sildenafil delays the intestinal transit of a liquid meal in awake rats. Braz J Med Biol Res 2008; 41: 78-81.

Figure 1. Comparison of iv treatment (0.2 mL) with sildenafil (4 mg/kg) or vehicle (0.01 N HCl) on the intestinal transit of a liquid test meal in awake rats. Ten minutes after treatment, rats were fed by intraduodenal injection a 1.0-mL bolus of saline labeled with ^99mtechnetium and killed 20, 30, or 40 min later. A, Typical radioactivity scintiscans and plots of fractional retention of the marker throughout the gut, from the stomach and proximal duodenum (segment number 1) to the large bowel (segment number 7) of sildenafil- (full line) or vehicle (broken line)-treated rats, studied at 40 min after the meal. GIT = gastrointestinal tract. B, Values of the geometric center of radioactivity distribution from the stomach and proximal duodenum (segment number 1) to the large bowel (segment number 7) of awake rats treated with sildenafil (filled squares) or vehicle (open squares). Horizontal bars are medians. P < 0.05 compared to control (Mann-Whitney U-test).