Confocal sections of LV free wall. Confocal microscopy was used to image fluorescent antibody labels to identify type I & type III collagen, and phalloidin-rhodamine labelled F-actin in sections (30 μm) from the LV free wall. (A) Shows representative LV wall cross-sections (16 х objective) labelled for F-actin (red) and type I collagen (green) in control (i), diabetic (ii) and TETA-treated diabetic rats (iii) (n = 7/group). Diabetic rats had decreased LV wall thickness and increased collagen labelling compared to controls; TETA-treatment normalized type I collagen labelling. (B) illustrates representative longitudinal sections of LV tissues (40 х objective, zoom 3) from control (i), diabetic (ii) and TETA-treated diabetic rats (iii). Diabetic rats displayed disrupted F-actin structure whereas TETA-treatment maintained F-actin integrity.