Table 3.

Histological measurements.

Group	LV muscle area (mm2)	Scar area (mm2)	IVS thickness (mm)	Capillary density (count/mm2)
C	53.6±4.6	12.8±5.2	1.8±0.4	150.3±50.0
ET	60.6±15.0	4.1±2.6‡	2.8±1.0§	146.6±38.9
M	64.2±8.1	8.2±3.1	2.2±0.6	168.1±50.7
IR	65.9±11.7	8.1±2.0	2.2±0.4	196.1±22.0
M+N	62.0±3.3	13.7±5.4	2.2±0.2	135.4±43.0
ET+M	65.4±11.0	7.5±3.2	3.1±0.4¶|	136.2±46.9
ET+N	85.1±5.7*	31.5±11.5†	2.8±0.4	145.3±22.3

Results are shown as mean±SD.

^*p<0.05 vs. all other groups;

^†p = 0.0001 vs. all other groups;

^‡p = 0.01 vs. C and vs. M+N;

^§p<0.05 vs C.

^¶p<0.05 vs C, M and IR.

LV  =  left ventricular; IVS  =  interventricular septum; C  =  control; ET  =  exercise training; M  =  morphine; IR  =  intermittent ischemia-reperfusion; M+N  =  morphine plus naloxone; ET+M  =  exercise training plus morphine; ET+N  =  exercise training plus naloxone.