Tissue Damages And Expressions Of Hsp47/Hsp60 In Transported Piglets

12 Pietrain and 24 Erhualian piglets were chosen in the experiment, all piglets were raised at the same condition. When the avoirdupois of all piglets reached 20±1 kg, 6 Pietrain and 12 Erhualian were chosen as transported team, loaded onto a truck and individually housed in separate cages for a transportation of 2 h in a common pig transport trailer (the speed was 60 km/h), the rest were maintained under normal conditions and used as the control. At the end of the journey, all animals were administered general anaesthesia pentobarbital sodium (10 mg/kg) and killed according to normal commercial practice in a dissection room. Blood was collected and separated for sera, the sera obtained were frozen at -20℃for the detection of creatine kinase (CK) and aspartate aminotransferase (AST). The specimens (heart, liver, kidney, stomach) for histopathology and immunohistochemical detections were fixed in 4% paraformaldehyde, and those for quantifying the levels of Hsp47 and Hsp60 were quickly frozen in liquid nitrogen, and stored at -70℃.Results of colorimetric method showed that: the level of CK in Erhualian piglets was increased (P<0.05) and that in Pietrain piglets was increased too (P<0.01), after transport stress, the activity of AST in both Erhualian and Pietrain piglets was increased (P<0.05).Results of hematoxylin and eosin staining (HE) showed that, after transportation, the heart, liver, kidney and stomach of Erhualian and Pietrain piglets displayed damages at different levels. Damages of Pietrain piglets were more obviously, obvious damages could not be seen in the control of these two breeds.Results of immunohistochemistry showed that, Hsp47 were predominantly expressed in the cytoplasm and nucleus of cardiomyocytes, the endothelial cells of central vein and hepatic sinusoid in liver, in the endothelial cells of renal glomeruli and epithelial cell of distal convoluted tubule in kidney, in the connective tissues of the mucosa and submucosa in stomach; Hsp60 positive signals were detected in cytoplasm of myocardial cells and hepatocytes; in cytoplasm of epithelium of the renal tubule and fundic gland. Hsp60 expression was more prominent in the cytoplasm of intact cells than in that of degenerated cells, this phenomenon was more obviously in heart and liver.Results of enzyme linked immunosorbent assay (ELISA) showed that, after the transportation for 2 h, changes of Hsp47 in heart and liver of two breeds were not significant, the expressions of Hsp47 in kidney and stomach of Pietrain transported piglets were significantly higher than those of control ones (P<0.05), but it had no obvious difference in Erhualian piglets; the expressions of Hsp60 in heart of two breeds were significantly lower in heart (P<0.05), but higher in stomach (P<0.05), Hsp60 was reduced significantly (P<0.05) in liver of Pietrain piglets, but that was no obvious difference in Erhualian piglets, no differences were observed in kidney of these two breeds.According to several studies above, conclusions were got as follows: (1) Damages of Pietrain piglets were more obviously than Erhualian piglets, it demonstrated that as sensitive to stress, Pietrain piglets were more easy to suffer from transport stress. (2) Hsp60 expression was more prominent in the cytoplasm of intact cells than in that of degenerated cells, it is suggested that tissue-specific Hsp60 expression may be linked to tissue damage in response to transport stress. (3) The expressions of Hsp47 in kidney and stomach of Pietrain transported piglets were significantly higher than those of control ones (P<0.05), Hsp60 was reduced significantly in liver of Pietrain piglets (P<0.05), but that was no obvious difference in propotional tissues of Erhualian piglets; it demonstrated that Erhualian piglets were more adaptation to stress and as a breed which was sensitive to stress, Hsp47 and Hsp60 in tissues of Pietrain piglets were more like to express abnormaly. (4) After the transportation of 2 h, changes of Hsp47 and Hsp60 in heart, liver, kidney and stomach of these two breeds piglets seemed no regularity, and the significance level of differential was difference, it demonstrated that heat shock proteins in different families had different mechanism of actions in playing the role of tissue protection. Even though a heat shock protein, maybe its mechanism of protect action was difference in different tissues, it implied that Hsps had tissue dependence.