This study determined whether exercise training prevents pathological hypertrophy in the left ventricle by modulation of myocardial and apoptosis-associated genes. We used spontaneously hypertensive rats (n=15, non-exercise SHR), exercise-trained SHR (n=15, treadmill exercise for 12 weeks), and sedentary Wistar-Kyoto (WKY) rats (n=15). Exercise-trained SHR expressed adaptive changes such as reduced body weight, heart rate, blood pressures, left ventricle wall thickness, lipid profiles, and homocysteine level. The mRNA expression of angiotensin converting enzyme, endothelin-1, and brain natriuretic peptides in the heart was lower in the exercise-trained SHR and in the WKY than in the non-exercise SHR, whereas mRNA expression of caveolin-3 and eNOS in the heart was higher. Bcl-2 protein was higher in the exercise-trained SHR than in the WKY and the non-exercise SHR. In contrast, Bax protein levels were lower in the exercise-trained SHR and in the WKY than in the non-exercise SHR. Furthermore, the levels of the active forms of caspase-3 (20 kDa) were lower in the exercise-trained SHR and in the WKY than in the non-exercise SHR. These findings suggest that exercise training prevents pathological hypertrophy in the left ventricle by modulation of myocardial genes and that it interferes with a signal transduction pathway of apoptosis secondary to the pathological cardiac hypertrophy.

Whereas most debates about growth controls have focused primarily on the impacts of land and house prices, this study examines anticipated job and output losses. Using the example of the proposed nonresidential and residential controls approved by the voters of Pasadena, California, as a case study, the authors employ a spatial allocation/regional input-output model (the Southern California Planning Model) that allocates highly disaggregated sectoral impacts (direct, indirect, and induced) to 219 zones (cities and unincorporated areas) in the Los Angeles metropolitan region. The largest economic losses are the result of denied nonresidential construction, and these are cumulative over the ten years of the proposed ordinance (now defunct after the 1992 elections). The lowest-skilled occupational groups are the hardest hit in terms of lost jobs, and almost three fifths of the employment losses occur in the city of Pasadena itself. These results offset the favorable claims for growth controls made by their advocates.

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