RESUMEN
<p><b>OBJECTIVE</b>To study the mechanism of the effect of low-frequency rotary constant magnetic field on high-fat and high-protein diet-induced fatty liver in rats.</p><p><b>METHODS</b>Fatty liver model was established in SD rats by feeding on a high-fat and high-protein diet daily. The enzyme activity changes in the serum and liver homogenate were detected at 10, 14, and 18 weeks, and the pathological changes of the liver were observed with optical and electron microscopy.</p><p><b>RESULTS</b>In magnetic field intervention group, the concentration of alanine aminotransferase and aspartate transaminase were significantly decreased, and the activity of lipoprotein lipase, hepatic lipase, superoxide dismutase and the concentration of malondialdehyde in the liver homogenate were significantly increased. Under optical microscope and electron microscope, the rats in the model group showed diffusive adipose degeneration in the hepatic cells with large lipid droplets, which became large vacuoles after fat extraction, indicating fatty necrosis. In magnetic field intervention group, remarkably smaller lipid droplets and lessened hepatic cell adipose degeneration were observed.</p><p><b>CONCLUSION</b>Low-frequency rotary constant magnetic field has beneficial effect on fat metabolism, leading to reduced lipid peroxidation and structural recovery of the degenerated hepatic cells.</p>