Effects of hypothermia on Ca2+∕calmodulin-dependent protein kinaseⅡ and cell autophagy in brain tissues after cardiac arrest and cardiopulmonary resuscitation in swine
10.3760∕cma.j.issn.0254-1416.2019.04.028
- VernacularTitle:亚低温对猪心脏停博复苏后脑组织钙调蛋白激酶Ⅱ和细胞自噬的影响
- Author:
Qijiang CHEN
1
;
Jiefeng XU
;
Xiaohong JIN
;
Chunshuang WU
;
Zilong LI
;
Moli WANG
Author Information
1. 宁海县第一医院ICU 315600
- Keywords:
Hypothermia;
induced;
Heart arrest;
Cardiopulmonary resuscitation;
Reperfusion injury;
Brain;
Ca2+∕calmodulin-dependent protein kinase Ⅱ;
Autophagy
- From:
Chinese Journal of Anesthesiology
2019;39(4):490-493
- CountryChina
- Language:Chinese
-
Abstract:
Objective To evaluate the effects of hypothermia on Ca2+∕calmodulin-dependent pro-tein kinase Ⅱ ( CaMKⅡ) and cell autophagy in brain tissues after cardiac arrest and cardiopulmonary re-suscitation ( CA-CPR) in swine. Methods Twenty-one healthy male white swine, weighing 33-40 kg, were divided into 3 groups using a random number table method: sham operation group ( group S, n=5) , CA-CPR group ( n=8) and hypothermia group ( group H, n=8) . The experimental model of CA-CPR was established in CA-CPR and H groups. The Swan-Ganz catheters were placed in the right femoral artery and vein to monitor the pressure of thoracic aorta and right atrium and body temperature and to collect blood sam-ples. A pacing catheter was advanced from the right external jugular vein into the right ventricle. Ventricu-lar fibrillation was induced by using a 1 mA alternating current through the pacing catheter. Once ventricular fibrillation was successfully induced, mechanical ventilation was discontinued for 8 min, and then CPR was initiated. Epinephrine 20 μg∕kg was intravenously injected at 2. 5 min of CPR, followed by repetition once every 3 min. Defibrillation was delivered at 5 min of CPR, and then spontaneous circulation was evaluated. If the spontaneous circulation was not restored, CPR was immediately resumed for 2 min, and then defibril-lation was delivered again. Mechanical ventilation was continued for 30 h after successful CPR. At 5 min af-ter successful resuscitation, body temperature was decreased to 33 ℃ by using a cooling blanket, then maintained at 33 ℃ until 24 h after resuscitation, and finally increased at a rate of 1℃∕h for 5 h in group H. The temperature was maintained at a normal level of 37. 5-38. 5 ℃ with the aid of a cooling blanket in S and CA-CPR groups. At 1, 6, 12, 24 and 30 h after resuscitation (T1-5), blood samples were collected from the femoral vein for measurement of the concentration of neuron specific enolase ( NSE) and S100βprotein in serum by enzyme-linked immunosorbent assay. Five animals in each group were then sacrificed, and brains were removed to determine the expression of CaMKⅡ, microtubule-associated protein 1 light chain 3 Ⅱ( LC3Ⅱ) and p62 in cerebral cortex by Western blot. Neurological deficit score was evaluated in the remaining three swine at 48, 72 and 96 h after resuscitation (T6-8) in CA-CPR and H groups. Results Compared with group S, the concentrations of NSE and S100β protein in serum were significantly in-creased at T1-5 , the expression of CaMKⅡand LC3Ⅱin cerebral cortex was up-regulated, and the expres-sion of p62 in cerebral cortex was down-regulated in CA-CPR and H groups (P<0. 05). Compared with group CA-CPR, the concentrations of NSE and S100βprotein in serum were significantly decreased at T3-5, the neurological deficit score was decreased at T6-8 , the expression of CaMKⅡand LC3Ⅱin cerebral cortex was down-regulated, and the expression of p62 in cerebral cortex was up-regulated in group H ( P<0. 05) . Conclusion The mechanism by which hypothermia alleviates brain injury after CA-CPR may be related to inhibiting CaMKⅡ activation and reducing cell autophagy in brain tissues of swine.
