[Increase of connective tissue in rat hearts under exposure to noise and with magnesium deficiency (author's transl)].

Only a small amount of noise caused, combined with a nutritional Mg deficiency, a significant increase of collagen in the myocard of rats. While Mg deficiency or noise each for its own had no effect, the combination of both had a noxious effect. The results of these experiments give a hint to a correlation between collagen-increase in the myocard and an increase of urinal Catecholamine during the same time.