title: Comparison of UW solution and St. Thomas' solution in the rat: importance of potassium concentration.
abstract: BACKGROUND
  University of Wisconsin solution (UW) is in limited clinical use for heart transplantation, but there are doubts about its efficacy and concerns about the effect of its high K+ concentration on endothelium. St. Thomas' solution with or without aspartate is widely used and is of proven efficacy.
  
  
  METHODS
  Using a modified (starch-free) variant of UW (MUW) we studied: (1) recovery of function with UW compared with aspartate-containing St. Thomas' solution; (2) effect of elevation of K+ in St. Thomas' solution to the level in UW; and (3) effect of reduction of K+ in UW and addition of Ca2+ or aspartate. Isolated rat hearts underwent 7 hours of arrest at 1 degrees C using MUW with or without 20 mmol/L aspartate or using aspartate-containing St. Thomas' solution.
  
  
  RESULTS
  Functional recovery with MUW (51.8% +/- 2.5%) was superior to that with aspartate-containing St. Thomas' solution (37.1% +/- 4.3%; p < 0.01). Addition of aspartate to MUW had no effect. During 6 hours of arrest, lowering the K+ in MUW from 125 mmol/L to 20 mmol/L reduced functional recovery from 59.9% +/- 4.2% to 42.3% +/- 4.3% (p < 0.01). The addition of 1 mmol/L Ca2+ had no effect. Elevation of K+ in St. Thomas' solution produced more rapid arrest but no improvement in recovery.
  
  
  CONCLUSIONS
  The protective effect of starch-free UW is greater (+13%) than that of aspartate-enriched St. Thomas' solution. Reduction of K+ in UW to lessen possible deleterious effects would decrease its protective effect by about 30% to a level comparable with that of St. Thomas' solution.
authors.affiliation: Baker Medical Research Institute, Alfred Hospital, Melbourne, Victoria, Australia.
authors.forename: F L
authors.initials: FL
authors.lastname: Rosenfeldt
authors.forename: R A
authors.initials: RA
authors.lastname: Conyers
authors.forename: P
authors.initials: P
authors.lastname: Jablonski
authors.forename: L
authors.initials: L
authors.lastname: Langley
authors.forename: S M
authors.initials: SM
authors.lastname: Richards
authors.forename: G
authors.initials: G
authors.lastname: Self
authors.forename: V
authors.initials: V
authors.lastname: Marshall
mesh_terms: D000818:Animals; D001224:Aspartic Acid / Q000032:analysis; D001639:Bicarbonates / Q000737:chemistry / Q000494:pharmacology; D002118:Calcium / Q000032:analysis; D002122:Calcium Chloride / Q000737:chemistry / Q000494:pharmacology; D002314:Cardioplegic Solutions / Q000737:chemistry* / Q000494:pharmacology; D003326:Coronary Circulation; D006321:Heart / Q000187:drug effects; D006324:Heart Arrest, Induced; D066298:In Vitro Techniques; D008274:Magnesium / Q000737:chemistry / Q000494:pharmacology; D008297:Male; D019188:Organ Preservation Solutions; D011188:Potassium / Q000032:analysis*; D011189:Potassium Chloride / Q000737:chemistry / Q000494:pharmacology; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D012965:Sodium Chloride / Q000737:chemistry / Q000494:pharmacology; D012996:Solutions / Q000737:chemistry* / Q000494:pharmacology; D018709:Statistics, Nonparametric
chemical_list: D001639:Bicarbonates; D002314:Cardioplegic Solutions; D019188:Organ Preservation Solutions; D012996:Solutions; C041711:St. Thomas' Hospital cardioplegic solution; C071285:hydroxyethyl starch-free University of Wisconsin solution; D001224:Aspartic Acid; D012965:Sodium Chloride; D011189:Potassium Chloride; D008274:Magnesium; D002122:Calcium Chloride; D011188:Potassium; D002118:Calcium