Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.7.10.1 (ERK)
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The cardiac conduction system is considered to be particularly resistant to ischaemia. Nevertheless, following open heart surgery with short periods of ischaemia disturbances in AV conduction or ventricular arrhythmia have been reported. We compared the ultrastructure of AV node and working myocardium following 30 min global ischaemia at 25 degrees C, during pure ischaemia and with HTK cardioplegia qualitatively and morphometrically. After 30 min of pure ischaemia, interstitial and intracellular oedema together with considerable changes in organelles in AV nodes predominate over mainly cellular oedema in working myocardium. Sometimes irregular overcontractions of sarcomeres occur in the AV node, though very seldom in working myocardium. In pure ischaemia, mitochondrial swelling is comparable in both types of tissue. Following HTK cardioplegia and 30 min ischaemia, cellular oedema and mitochondrial swelling are significantly reduced in AV nodal cells and working myocardium, but remain more extensive in the AV nodes. Irregularities in the contractile state of sarcomeres are not observed. The extent of the ultrastructural alterations corresponds to the degree of metabolic change in the working myocardium. Thus, despite considerable differences during pure ischaemia and HTK cardioplegia, ultrastructurally the AV nodal cells do not display a greater resistance to ischaemia than working myocardium.
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PMID:Ultrastructural effects induced by global ischaemia on the AV node compared with the working myocardium. A qualitative and morphometric investigation on the canine heart. 210 49

The cardioplegic HTK-solution (Bretschneider) has not been used in human liver transplantation as yet. Herein the first results obtained from 14 patients with HTK-preserved liver grafts are presented. The suitability of HTK-solution could be shown. All grafts functioned primarily except one, where initial non-function was obviously due to donor reasons. The early postoperative peak values of transaminases as a sign of ischemic damage were average and similar to the values of other flushout solutions. Using HTK primary function could be achieved even in livers prospectively assessed as only of fair quality, and livers with poor donor function tests (MegX) functioned from the beginning. HTK-solution therefore seems to allow widening of the acceptance criteria for donor livers. It was not the aim of this trial to extend cold ischemic time, but 3 livers with 11 h and 12 h 25 showed immediate function. How far cold ischemic time can be extended is a still open question. All livers were rapidly cooled and homogeneously flushed out due to the low viscosity of HTK-solution. All livers had a soft consistency after perfusion indicating a low degree of cell edema. HTK therefore is an effective solution for liver preservation.
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PMID:HTK-solution (Bretschneider) for human liver transplantation. First clinical experiences. 210 16

In order to evaluate the importance of glycogen for the hepatic tolerance to ischemia, livers of swine fed a glucose-potassium solution for premedication were perfused with either Bretschneider's HTK-solution (histidine-tryptophan-ketoglutarate) or with Euro-Collins-solution (EC) prior to subsequent ischemia at 25 and 5 degrees C. During ischemia, in regular intervals or continuously, energy rich phosphates, lactate, intrahepatic pH and the electrical impedance of liver tissue were determined. The results were compared with corresponding data from swine which had starved for 48 h. Corresponding to the higher glycogen content, energy supply during ischemia was markedly improved by the premedication. Despite high amounts of glucose in the EC-solution, energy supply after glucose-potassium premedication was no better with EC-solution than with HTK-solution. Moreover, glucose uptake led to concomitant cellular water uptake. Electrical impedance measurements during ischemia mirrored improved energetical protection by the glucose-potassium premedication.
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PMID:Glycogen effects on energy state and passive electric properties of liver during protection. 211 13

Endothelial cell damage caused by myocardial cardioplegic solutions (Bretschneider HTK and St. Thomas' Hospital No. 2) or renal and hepatic cold storage solutions (modified Collins and University of Wisconsin solution) was assessed in monolayer cultures of adult human venous endothelial cells at 4 degrees to 10 degrees C with phase-contrast microscopy. St. Thomas' Hospital solution caused the cells to contract, resulting in disruption of monolayer integrity and opening of intercellular gaps, and resulted in a 24-hour postexposure survival of 51.0% +/- 2.4%. Bretschneider HTK solution altered cellular morphology less and produced the best postexposure survival (80.2% +/- 2.6%; p less than 0.001). Although morphology was altered the least with University of Wisconsin solution, postexposure survival with this solution, which was similar to that with modified Collins solution, was superior to that with St. Thomas' (p less than 0.01) but inferior to that with Bretschneider HTK (p less than 0.05). The superior protection provided by Bretschneider HTK was due to its additives histidine, tryptophan, and KH-2-oxygluterate (p less than 0.005), and to its low chloride content (p less than 0.005). Furthermore, modifying St. Thomas' solution by decreasing its chloride content improved cell survival to 71.2% +/- 2.3% (p less than 0.001). Normothermic (37 degrees C) exposure to Bretschneider HTK, modified Collins, and University of Wisconsin solution was cytotoxic, whereas normothermic exposure to St. Thomas' cardioplegia was not. In conclusion, the preservation solution that is the least harmful to endothelial cells at hypothermia is Bretschneider HTK cardioplegic solution.
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PMID:Endothelial cell toxicity of solid-organ preservation solutions. 212 22

There is a rule of thumb that an ischaemia time of 6 hours should not be exceeded when preserving a free flap. Microsurgical reconstructions sometimes require a long operation time and a long tolerance of ischaemia of the free flap. Using Bretschneider's HTK solution for the intraoperative cold storage of free flaps with a temperature of 5-7 degrees C, an ischaemia time of 12 hours should not affect the free flap, and hence the time limit of the ischaemic tolerance looses its importance. Based on Bretschneider's research results of cardioplegia and of the ischaemic tolerance of the kidney and the liver, we chose the HTK solution for the intraoperative protection of free microsurgical flaps.
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PMID:[Intraoperative protection of free microsurgical transfer flaps: "cold storage" in HTK-1 solution]. 212 25

So far two methods for prolonging the tolerance of renal ischemia are available: 1) surface cooling with crushed ice and 2) perfusion cooling with an extracellular-like solution. Both methods use only the principle of reducing metabolism through cooling. While rewarming during surgery the ischemic protection is lost, or the kidney must be cooled once again. Therefore, a new preservation solution should reduce energy consumption due to its composition in addition to cooling. For open heart surgery, the HTK solution by Bretschneider is already used clinically. In 71 dog kidney experiments, the ischemic time kidneys could tolerate was prolonged by this solution from 15 to 120 min at 35 degrees C and from 45 to 360 min at 25 degrees C. After 2 h of ischemia at 30 degrees C glomerular filtration rate was about 20 ml/min.100gww within 3 h of reperfusion. After six postoperative days the filtration rate was 40 ml/min.100 gww. No ischemic damage could be recognized by histological investigations. The clinical effectiveness of this method was shown in 7 clinical applications. Ischemic duration lasted up to 113 min, and blood creatinine was between 0.8 and 2.4 mg% at the 6th postoperative day. Use of this preservation technique thus leads to improved kidney function immediately following operation. Longer ischemia can be tolerated by a kidney thus protected, and using this technique excellent visibility can be achieved during intrarenal surgery, simplifying, for example, tumor extirpation.
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PMID:A new method for conservative renal surgery--experimental and first clinical results. 212 22

In ischemic canine kidneys protected by Bretschneider's HTK solution the glycolytic lactate production is limited by a low renal substrate content. However, for anaerobic energy supply ischemic organs depend on glycolysis. To evaluate the role of glycolysis in renal protection, the relationship between lactate production and anaerobic energy supply was examined in protected kidneys of dogs, sheep, and swine. Additionally, in canine kidneys an attempt was made to improve anaerobic energy provision by adding glucose to the protective solution. The results were as follows: (1) According to increasing lactate production from swine to dog to sheep, intraischemic ATP decay was delayed least in swine and most in sheep. (2) Glucose addition (10 mM) to the HTK solution roughly doubled the time for ATP to fall to 1 mumol/g dry wt (tATP) in dogs. (3) The greater the lactate production in all three species, the lower the decrease in SAN (ATP + ADP + AMP) from 5 to 120 min of ischemia. (4) A glucose additive in the protective solution led to a significant (p less than .005) increase of SAN in dogs at 120 min of ischemia. A sufficient substrate supply seems to be an essential component of a reliable renal protection.
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PMID:Glucose content and efficiency of glycolysis in protected ischemic kidneys of different species. 212 43

The influence of cardioplegic arrest (single or multidose cardioplegia) and subsequent long-term cold storage on myocardial high energy phosphate content was studied in 29 dogs divided into 6 groups of experiments. Three cardioplegic solutions were tested: Bretschneider HTK (intracellular-type solution), St. Thomas' Hospital and N.I.H. solutions (both extracellular-type solutions). In group I, II and III single dose cardioplegic arrest with respectively St. Thomas' Hospital, Bretschneider HTK and N.I.H. solutions was carried out and excised hearts were stored at 0.5 degrees C for 24 hours. In group IV-Bretschneider HTK and in group V-N.I.H. solutions were used for cardioplegic arrest and intermittent perfusion of the cooled hearts at 4, 8 and 12 hours of storage (multidose cardioplegia). In group VI, after cardioplegic arrest with Bretschneider HTK solution, different temperatures of storage (0.5 degrees C, 12 degrees C and 18 degrees C) were studied. Myocardial content of ATP and creatine phosphate was evaluated by means of bioluminescence techniques from serial left ventricular biopsies taken prior to aortic cross-clamping and after 1, 2, 3, 4, 5, 6, 8, 10, 12 and 24 hours. In group I ATP was significantly lower than in groups II and III after 6 h (p less than 0.005). After 24 hours of storage ATP-levels were significantly higher (p less than 0.05) after multidose Bretschneider HTK cardioplegia or N.I.H. cardioplegia than after single dose N.I.H. or St. Thomas' cardioplegia. There was no significant difference in ATP content between multidose Bretschneider and multidose N.I.H. cardioplegia.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Long-term preservation of donor hearts: the effect of intra- and extracellular-type of cardioplegic solutions on myocardial high energy phosphate content. 213 19

The ischemic damage following liver transplantation (LTX) is predominantly located at the endothelial cell level and is a major cause for a disturbance of microcirculation. The present study was designed to test the hypothesis that changes in the quality of organ preservation are correlated with changes in microcirculation: 16 pigs underwent LTX, preservation by Bretschneider's HTK-solution (Histidin, Tryptophan, alpha-Ketoglutarat) complemented by indomethacin (50 mumol/L). Cold ischemia times were 9 hr (n = 8) and 18 hr (n = 8), respectively. Using the H2-clearance technique, hepatic microcirculation was measured before, 30 min, and 20 hr after LTX. Normal tissue perfusion was 107 +/- 16 ml/100 g/min, at 30 min posttransplantation 91 +/- 13 ml/100 g/min in the short-term and 48 +/- 7 ml/100 g/min in the long-term preservation group. Whereas no animal of the long-term preservation group survived longer than 8 hr, all animals of the short-term preservation group survived, and tissue perfusion could be measured 20 hr postoperatively (101 +/- 19 ml/100 g/min). At 30 min postoperatively, all surviving animals had tissue perfusion rates greater than 70, and all nonsurvivors had values below 60 ml/100 g/min. We conclude therefore that the extent of decrease of microcirculation after LTX may be a useful predictor of organ function and survival.
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PMID:Evaluation of preservation damage after porcine liver transplantation by assessment of hepatic microcirculation. 225 66

Imperative indications for organ-sparing surgery of renal tumors are given mainly in existing or imminent restriction of renal function. Organ-sparing excision of renal tumors under in-situ protection with HTK-solution compared with operations without protection have the following advantages: 1. reduced blood loss, 2. longer ischemia, 3. better tissue differentiation with benefit for radicality, 4. shorter hospital stay.
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PMID:["Imperative indication" for organ-preserving kidney tumor surgery]. 226 26


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