1) Nine male rabbits 38 months old were concurrently loaded with 3 different treatments i. e., N2 gas inhalation, norepinephrine in injection and cholesterol oral administration, and left coronary anterior descending branch (LCA 5) was observed histochemically and determined for smooth muscle cell, elastin, collagen, acid mucopolysaccharides and glycoproteien in comparison with 8 healthy normal rabbits of the same age.
2) The histology of the indurative group presented obivious histo-lesional findings such as atrophy and necrosis of the smooth muscle cells (SMC), swelling and stratified rupture of the inner elastic membrane, loses in content of medial elastin (EL) and collagen (CL) and their transfer from the tunica externa, and compensatory increases in content of acid mucopolysaccharides (AMPS) and glycoprotein (GP).
3) The results of the determination made of these 5 constituents revealed that the healthy normal group and the indurative group showed 65.4±7.9 and 46.7±7.5 (p<0.001) of SMC, 9.6±0.88 and 12.2±2.78 (p<0.05) of EL 25.7±4.02 and 35.6±3.86 (p<0.001) of CL, 14.4±1.7 and 20.2±2.85 (p<0.001) of AMPS and 22.8±5.9 and 31.6±7.5% E of GP, respectively, the indurative group showed significantly less content of SMC and significantly more contents of EL, CL, AMPS and GP than the healthy normal group.
