Effects of short-term, high-intensity and long-term, moderate-intensity exercise on biochemically assessed sarcoplasmic reticulum (SR) ATPase protein were analyzed in muscle homogenates of the rat after treadmill runs to exhaustion (avg, time to exhaustion 2 min 48 sec and 1 h 29 min, respectively) . The exercise-induced changes in SR Ca²⁺ -ATPase activity were muscle type-specific. After short-term exercise, a decrease in the activity occurred in the soleus muscle and the superficial region of the vastus lateralis muscle whereas long-term exercise depressed the rate of ATP hydrolysis in the soleus muscle and the deep region of the vastus lateralis muscle. The concentration of fluorescein isothiocyanate, a competitor at the ATP-binding site, for 50% inhibition of SR Ca²⁺ -ATPase activity fluctuated only in the soleus muscle subjected to short-term exercise ; it was increased by 31%. This change occurring in the soleus muscle would elevate SR Ca²⁺ -ATPase activity at a given concentration of ATP. The results presented here suggest that acute short-term exercise to exhaustion may exert a remarkably inhibitory factor on SR Ca²⁺ -ATPase protein of slow-twitch muscle, which can overcome the positive effect probably arising from the phosphorylation of the phospholamban.

In order to clarify the effect of exercise on the walking performance and the muscle volume in lower limbs, elderly athletes long continuing to be trained and untrained elderly were compared with regard to their muscle cross-sectional area (CSA) of m. psoas major, thigh muscle and crus muscle and their walking ability. The subjects used consisted of thirty-six 80's-aged male and 70's-aged female elderly athletes and twenty-four elders having no regular exercise (control male group : CM, control female group : CF) . The elderly athletes were further divided into two groups in accordance with their results of Japan Fitness Test (high performance male group : HPM, low performance male group : LPM, high performance female group : HPF, low performance female group : LPF) . The walking performance was evaluated by analyzing their walking speed, stride-length and step rate during walking along a 15 m-strip of passage at normal and fast paces using videotaping. The muscle CSA was determined at m. psoas major, thigh muscle (extensors and flexors) and crus muscle (m. tibialis anterior and m. triceps surae) using MRI. As for the walking speed and stride-length at the normal pace, only HPM and HPF showed significantly higher values than CM and CF (male : p<0.05, female : p<0.01) . Meanwhile at the faster pace, HPF and LPF showed significantly higher values than CF in female (HPF : p<0.01, LPF : p<0.05) and in the case of males, only HPM have a higher value only of the walking speed than CM (p<0.05) . The CSA of m. psoas major in HPM and HPF significantly higher than that in CM and CF (all p<0.05), while in CSAs of knee extensor muscles and m. triceps surae, the statistical differences were not consistent among male and female groups. The results suggested that greater muscle mass of m. psoas major could influence higher walking speed in elderly people, and might be affected by regular exercise training.

Since January, 1981 to December, 1990, eight patients (one male, 7 female) of Stanford A type aortic dissection underwent surgical treatments with deep hypothermic circulatory arrest. The average was age 59.6 years (range 50 to 72 years). All of them were diagnosed with UCG and/or CT before operation. Two cases had already been in shock state due to cardiac tamponade. Three cases had aortic insufficiency and one had neurological deficit. After median sternotomy, right atrial-femoral artery bypass was established. Right atrium was incised and coronary sinus was cannulated. Then retrograde coronary infusion of cardioplegic solution was employed at a continuous flow rate of 20ml/kg/hr. The mean rectal temperature was 19.6°C and the mean circulatory arrest time was 35.5min (22-58min). Two of eight cases died, because of DIC followed by necrotizing enteritis at 28th postoperative day, and prolonged shock state before operation. The rest were all survived without any neurological deficits. There were no severe complications related to deep hypothermia. We concluded that deep hypothermic arrest is safe and simple method, allows good inspection of operative field and makes it easier to repair the dissected aorta.

A rare case of ascending aortic aneurysm due to post stenotic dilatation associated with aortic valve stenosis in a 67-year-old man was treated surgically. Aortic valve stenosis with a systolic pressure gradient of 87mmHg was recognized. Thoracic aortogram and CTscan revealed dilatation of the ascending aorta which was 85mm in diameter. Because the ascending aorta was obviously dilated and its wall was thin at operation, the possibility of rupture was considered to be high. Aortic valve replacement using a 23mm SJM prosthetic valve was performed and graft replacement of the ascending aorta with a 28mm collagen-shield graft was carried out simultaneously. He was discharged in excellent condition on the 45th postoperative day. Pathological examination of the aortic wall revealed an apparently thin wall, but the three layer structure of the wall and elastic laminae were well preserved. Inflammation and atherosclerotic findings were not detected. It was concluded that post stenotic dilatation associated with aortic valve stenosis can develop aneurysm that eventually requires surgical treatment.

BACKGROUND AND OBJECTIVES: Reactive oxygen species (ROS) mediate various signaling pathways that underlie vascular inflammation in atherogenesis and cardiovascular diseases. Cardiac rehabilitation (CR) has a variety of multiple beneficial effects, including anti-inflammatory effects. The purpose of the present study was to investigate the effects of CR on ROS in patients with cardiovascular diseases. SUBJECTS AND METHODS: The serum level of derivatives of reactive oxidative metabolites, an index of oxidative stress, was measured in 100 patients with cardiovascular diseases before, and, subsequently, 3 and 6 months after, CR. A biological antioxidant potential (BAP) test was applied to assess the antioxidant power of the serum. RESULTS: The resting reactive oxidative metabolite levels decreased 3-6 months after CR {pre: 351+/-97 Carratelli unit (CARR U), 3 months: 329+/-77 CARR U, 6 months: 325+/-63 CARR U, all p<0.01} with the increase of the percentage of the predicted values of VO2 peak and the percentage of the predicted values of VO2 at the anaerobic threshold (VO2 AT) and the decrease of the B-type natriuretic peptide (BNP). The BAP test and antioxidative/oxidative stress ratio increased 6 months after CR. The % changes of the antioxidative/oxidative stress ratio was positively correlated with the % changes of VO2 AT, and negatively correlated with the % changes of the BNP. CONCLUSION: These results suggest that intensive supervised CR significantly improved exercise capacity, which may be attributable to an adaptive response involving more efficient oxidative metabolites or the increased capacity of endogenous anti-oxidative systems in patients with cardiovascular diseases.
Anaerobic Threshold ; Antioxidants ; Atherosclerosis ; Cardiovascular Diseases ; Exercise Therapy ; Humans ; Inflammation ; Natriuretic Peptide, Brain ; Oxidative Stress ; Oxygen Consumption ; Reactive Oxygen Species