Metabolic and renal parameters of control, diabetic and treated diabetic rats.

<p>Data are means ± SD, n = 8–10/group, ^*p<0.05 vs. C; ^§p<0.05 vs. D, ^**p<0.01 vs. C; ^§§p<0.01 vs. D, ^***p<0.001 vs. C; ^§§§p<0.001 vs. D; respectively. UD–undetectable.</p

Western blot analysis of Na/K ATPase (NKA).

<p>Aldosterone antagonists were the most effective in decreasing diabetes and hyperglycemia induced elevation of tubular NKA protein level. Top panel: Representative examples of Western blot analysis. Lower panels: <i>A</i>: Densitometric analysis of NKA protein levels in kidney homogenates of control, diabetic and treated diabetic rats. <i>B</i>: Densitometric analysis of NKA protein levels in HK-2 tubular cells. Bar graph represents densitometric analysis from multiple experiments. Data represent means ± SD; *p<0.05 <i>vs</i> Control; §p<0.05 <i>vs</i> Diabetes, respectively; (bars show means±SD; n = 8–10/group). IOD – integrated optical density.</p

Renal histopathology in control, diabetic and treated diabetic rats.

<p>Aldosterone antagonists were the most effective in attenuating the structural lesions of DN. Representative PAS staining of kidney sections (40x magnification; scale bar –50 μm): non-diabetic control (A), STZ-induced diabetic (B), Enalapril (E), Losartan (F), Spironolactone (G) and Eplerenone (H) treated diabetic rats (n = 8–10/group). Long, wide headed arrows point on mesangial matrix; long, narrow headed arrows on arterioles. Armanni-Ebstein lesions are marked with short, wide headed arrows. <i>C</i>: Mesangial fractional volume values (Vv) are defined by the ratio of mesangial area/glomerular tuft area. The mesangial area is determined by assessment of PAS-positive and nucleus-free areas in the mesangium. *p<0.05 <i>vs</i> Control; §p<0.05 <i>vs</i> Diabetes, respectively; (bars show means ± SD). <i>D</i>: Arteriolar hyalinosis is defined by the average of hyalinized quarters of arterioles. The hyalin is determined by assessment of PAS-positive and nucleus-free areas within the arterioles. *p<0.05 <i>vs</i> Control; §p<0.05 <i>vs</i> Diabetes, respectively; (bars show means ± SD).</p

Confocal images of control, diabetic and treated diabetic rats.

<p>Aldosterone inhibitors prevented the mislocation of NKA induced by diabetes in proximal tubules. Representative pictures of immunofluorescence staining of kidney sections for Na/K ATPase (NKA, green) in control (A), streptozotocin-diabetic (B) and diabetic, Enalapril (C), Losartan (D), Spironolactone (E) and Eplerenone (F) treated rats (63x magnification; scale bar–10 μm). Nuclei are stained blue with Hoechst. PT-proximal tubule, DT-distal tubule, Bm-basal membrane, Lu – apical membrane at the lumen and Nucl – nuclei. Fluorescent signal intensity of NKA (green) generated from a line shown as red arrow in the merged image are shown on the bottom right of each panel.</p