Exercise Training Preserves Ischemic Preconditioning in Aged Rat Hearts by Restoring the Myocardial Polyamine Pool

Figure 3

Electron microscopy of the left ventricular ultrastructure. Representative hearts from the young IR control group (YC), young PC group (YPC), old IR control group (OC), old PC group (OPC), exercised old IR group (Ex-OC), exercised old PC group (Ex-OPC), and DFMO treatment groups (Ex-OC-I and Ex-OPC-I groups, DFMO was administered to the Ex-OC and Ex-OPC groups, resp.). per group. Magnification: ×10000.