Cerebral tumor necrosis factor α expression and long-term neurocognitive performance after cardiopulmonary bypass in rats

• Published in: The Journal of thoracic and cardiovascular surgery Vol. 138; no. 4; pp. 1002 - 1007
• Main Authors: Jungwirth, Bettina, MD, Kellermann, Kristine, DVM, Qing, Ma, MD, Mackensen, G. Burkhard, MD, Blobner, Manfred, MD, Kochs, Eberhard F., MD
• Format: Journal Article
• Language: English
• Published: New York, NY Mosby, Inc 01.10.2009; Elsevier
• Subjects: Anesthesia. Intensive care medicine. Transfusions. Cell therapy and gene therapy; Animals; Behavior, Animal; Biological and medical sciences; Brain - metabolism; Cardiology. Vascular system; Cardiopulmonary Bypass - adverse effects; Cardiothoracic Surgery; Immunohistochemistry; Male; Medical sciences; Memory; Pneumology; Psychomotor Performance; Rats; Rats, Sprague-Dawley; Reverse Transcriptase Polymerase Chain Reaction; Tumor Necrosis Factor-alpha - metabolism; 1; 25; CPB; 17; mean arterial pressure; cardiopulmonary bypass; 19; MAP; Performance evaluation; Rat; Cytokine; Rodentia; Gene expression; Long term; Encephalon; Cardiopulmonary bypass; Vertebrata; Mammalia; Animal; Anesthesia; Circulatory system; Cardiology; Performance; Tumor necrosis factor α
• ISSN: 0022-5223; 1097-685X
• DOI: 10.1016/j.jtcvs.2009.06.022

Objective Cerebral inflammatory reaction is discussed as a contributor to adverse cerebral outcome after cardiac surgery with cardiopulmonary bypass. This study was designed to determine the effect of cardiopulmonary bypass on both cerebral expression of tumor necrosis factor α and neurocognitive outcome in rats. Methods With institutional review board approval, 50 rats were randomly assigned to one of 3 groups: rats of the cardiopulmonary bypass group were subjected to 75 minutes of normothermic cardiopulmonary bypass. Sham-operated animals underwent identical preparation but were not connected to cardiopulmonary bypass, whereas rats of the control group were neither anesthetized nor cannulated. Ten rats per group survived 4 hours after cardiopulmonary bypass or the sham operation for immediate postoperative determination of tumor necrosis factor α–expressing cells (immunohistochemistry) and cerebral tumor necrosis factor α mRNA levels (polymerase chain reaction). The remaining animals survived 10 days for neurocognitive assessment by using the modified hole-board test and for analysis of cerebral tumor necrosis factor α activation in the late postoperative period. Results Expression of tumor necrosis factor α mRNA was increased 4 hours after cardiopulmonary bypass and the sham operation, with higher expression in the cardiopulmonary bypass group (χ2 [2] = 25.08, P < .001). Both experimental groups demonstrated larger numbers of tumor necrosis factor α–positive cells in the early and late postoperative periods (F [1] = 13.08, P ≤ .001) and an impaired neurocognitive performance on the first postoperative days compared with that seen in the control group (F [2, 24] = 4.26, P = .02). Conclusions Cerebral tumor necrosis factor α activation in both experimental groups during the early postoperative period was accompanied by transient neurocognitive impairment. Therefore cardiopulmonary bypass alone demonstrated no effect on cerebral inflammation and neurocognitive outcome.