Abstract: Objective To study cellular mechanism of cardiomyocytes injury in the early stage of crush injury by observing some effects of crush injury rat sera on cultured neonatal rat cardiomyocytes. Methods One to three days old neonatal rat cardiomyocytes were cultured in vitro and some effects of crush injury rat sera on beating rate, cell surface area, total protein content, 3H-Leu incorporation, intracellular calcium concentration ([Ca2+]i) and Fos protein expression were observed in cultured rat cardiomyocytes. Results Compared with normal rat serum group, crush injury rat sera decreased beating rate(beats/min) of cardiomyocytes from 88.3 to 26.4, cell surface area, total protein content, 3H-Leu incorporation, [Ca2+]i(nmol/L) and PI of Fos protein expression were increased. Conclusion Crush injury rat sera suppress cell beating, increase intracellular calcium, induce Fos protein synthesis and cause cell hypertrophy, which may cause cardiac injury in the early stage of rush injury.

Key words: crush, injury, cardiomyocyte, fos protein