Effect of L-arginine on NADPH-diaphorase activity in the renal outer medulla of control and diabetic rats.

C: control rats; D: diabetic untreated rats; D+A: diabetic rats treated with L-Arg; C+A: control rats treated with L-Arg. PT: proximal tubule; CD: collecting duct; THAL: thick ascending limb of Henle; OS: outer stripe; IS: inner stripe. NADPH-d staining values are expressed as optical density. Results are expressed as the mean ± SEM; “n” represents the total number of renal tubules analyzed. At least four animals of each group were used. Two-way ANOVA showed a statistically significant interaction between the effects of Diabetes and L-Arg treatment on NADPH-diaphorase activity in PT (p<0.001), CD (OS) (p<0.001), CD (IS) (p<0.05) and THAL (p<0.05). Bonferroni’s post-tests are showed in the table: **p<0.01 vs. C; ***p<0.001 vs. C; ###p<0.001 vs. C+A; &p<0.05 vs. D; &&&p<0.001 vs. D.