Aim of this article was studding secretory activity of myoengocrine cells of the heart in lesions under cadmium chloride. Used histological, ultrastructural, morphometrical methods. Established decreasing secretory activity myoengocrine cells of the heart pigs Vietnam breed under the influences of cadminum chloride on organism. Founded decreasing guantity secretory structures, percent young, ripe, increased diffundating granules. This changes dominated in the left atrium and testified about worse secretory activity myoengocrine cells, breaking synthesis natriiuretic hormone, inferiori-ty structural homeostasis.