Thyroid injury and its influencing factors after cardiopulmonary resuscitation in rats

Objective:To investigate the thyroid follicular cells injury and its influencing factors after cardiopulmonary resuscitation(CPR) in rats. Methods:Sprague-Dawley rat models of cardiac arrest(CA) and CPR were induced by asphyxiation combined with iced KCl. Forty male SD rats were randomized into 5 groups: control group (sham), post-resuscitation 3 h, 6 h,12 h, 24 h groups. Except for control group, rats were reperfused spontaneously for 3 h, 6 h, 12 h, 24 h after CPR. Serum concentration of T 3, T 4, thyroid-stimulating hormone (TSH) were determined in each group.The chromametery, the quantity of maleic dialdehyde(MDA) and enzyme activity of superoxide dismutase(SOD) and Na +-K +-ATPase in thyroid tissues were analyzed using chromametery in all groups. Results:Three hours after resuscitation, the serum concentration of T 3 and T 4 began to decline and remained in a lower level during the following subsequent 24 h, while there was only a transient decrease in the serum concentration of TSH on 12 h. Under TEM,injury of follicular epithelial cells was observed in post-resuscitation rats.MDA increased greatly after CPR(P0.05), meanwhile, enzyme activity of SOD and Na +-K +-ATPase in thyroid declined significantly compared to those of control group (P0.05). Conclusion:Acute thyroid follicular cells injury happens in rats after CPR. OFR-triggered lipid peroxidation, cellular energy metabolism disturbance and apoptosis may be principal manifestations of thyroid follicular cells injury in post-resuscitation rats.