Kavianipour M, Wikström G, Ronquist G, Waldenström A
Department of Cardiology, Norrland University Hospital, Umeå, Sweden.
Acta Physiol Scand. 2003 Sep;179(1):61-5. doi: 10.1046/j.1365-201X.2003.01145.x.
The validity of the microdialysis technique for experimental in vivo studies of myocardial energy metabolism is not known. To address this question interstitial levels of energy-related metabolites (lactate, adenosine, inosine and hypoxanthine) obtained by the microdialysis technique were compared with corresponding metabolites from myocardial biopsies at given intervals in a porcine heart model using different protocols of ischaemia and reperfusion.
In an open chest porcine heart model, interstitial levels of energy-related metabolites were monitored using the microdialysis technique. All animals (n = 23) were subjected to 120-min pretreatment followed by 40 min of regional ischaemia and 120 min of reperfusion. Tissue biopsies were obtained in the beginning, middle and at the end of the 40-min ischaemic period and at the end of the reperfusion period. Pretreatment consisted of either rest (group 1, n = 7), or rest for 90 min and one ischaemia/reperfusion (10 + 20 min) cycle (group 2, n = 9), or four ischaemia/reperfusion cycles (10 + 20 min each) (group 3, n = 7).
Interstitial levels of energy-related metabolites monitored by the microdialysis technique correlated with tissue biopsy levels of lactate (r = 0.90, P < 0.001), adenosine (r = 0.89, P < 0.001), inosine (r = 0.88, P < 0.001) and hypoxanthine (r = 0.91, P < 0.001), respectively, which were obtained by tissue biopsies at given time intervals. These significant correlations were valid regardless of the functional state of the myocardium.
We observed significant correlations between microdialysis probe levels and tissue biopsy levels of energy-related metabolites in both ischaemic and non-ischaemic tissue. These data assess the validity of the microdialysis technique (in the current setting) for studying dynamic changes of myocardial energy metabolism.
微透析技术用于心肌能量代谢的体内实验研究的有效性尚不清楚。为解决这一问题，在猪心脏模型中，采用不同的缺血和再灌注方案，在给定时间间隔内，将通过微透析技术获得的能量相关代谢物（乳酸、腺苷、肌苷和次黄嘌呤）的间质水平与心肌活检中的相应代谢物进行比较。
在开胸猪心脏模型中，使用微透析技术监测能量相关代谢物的间质水平。所有动物（n = 23）先接受120分钟预处理，然后进行40分钟局部缺血和120分钟再灌注。在40分钟缺血期开始、中间和结束时以及再灌注期结束时获取组织活检样本。预处理包括静息（第1组，n = 7），或静息90分钟并进行一个缺血/再灌注（10 + 20分钟）周期（第2组，n = 9），或四个缺血/再灌注周期（每个周期10 + 20分钟）（第3组，n = 7）。
微透析技术监测的能量相关代谢物的间质水平分别与组织活检中在给定时间间隔获得的乳酸（r = 0.90，P < 0.001）、腺苷（r = 0.89，P < 0.001）、肌苷（r = 0.88，P < 0.001）和次黄嘌呤（r = 0.91，P < 0.001）水平相关。无论心肌的功能状态如何，这些显著相关性均成立。
我们观察到在缺血和非缺血组织中，微透析探针水平与能量相关代谢物的组织活检水平之间存在显著相关性。这些数据评估了微透析技术（在当前设置下）用于研究心肌能量代谢动态变化的有效性。
