XTT-colorimetric assay as a marker of viability in cryoprocessed cardiac valve.
This study sought to evaluate the use of tetrazolium salt XTT reduction as an indicator of valvular viability in a cryoprocessed porcine cardiac homograft model. The XTT tetrazolium assays was based on the metabolic reduction of Sodium 3'-[1-(phenylamino-carbonyl)-3,4-Tetrazolium]-bis(4-methoxy-6-nitro) benzene sulfonic acid hydrate. The relationship between XTT reduction and: (1) leaflet tissue with various weight (n = 24); (2) morphometric evaluation (n = 30); (3) cadaveric ischemic intervals (n = 30); (4) freeze-thawing (n = 30) has been studied. The measurement of XTT reduction were significantly correlated with the weight of cardiac leaflets, in the range of 30 to 180mg (y=0.015x-0.063; r=0.99). Compared to morphometry of valvular damage, the reduction of mitochondrial enzymatic activity in cardiac leaflets was correlated with matrix cells without irreversible damage (r=0.89, P<0.005). The depletion of XTT reduction occurred dependent of ischemic time intervals. In general, freeze-thawing reduced more than 20% activity of mitochondrial dehydrogenase. We concluded that XTT tetrazolium assay is highly sensitive to determine valvular injury. The study demonstrated its potential for testing of cryopreserved cardiac valve.
Lu
J H
JH
Homograft Laboratory, Veterans General Hospital-Taipei, Taiwan, R.O.C.
Chiu
Y T
YT
Sung
H W
HW
Hwang
B
B
Chong
C K
CK
Chen
S P
SP
Mao
S J
SJ
Yang
P Z
PZ
Chang
Y
Y
D000818:Animals; D015415:Biomarkers; D003124:Colorimetry / Q000379:methods*; D015925:Cryopreservation; D006351:Heart Valves / Q000473:pathology / Q000502:physiology*; D008854:Microscopy, Electron; D008928:Mitochondria / Q000201:enzymology; D017202:Myocardial Ischemia / Q000378:metabolism; D010088:Oxidoreductases / Q000032:analysis / Q000378:metabolism*; D013552:Swine; D013778:Tetrazolium Salts / Q000737:chemistry*
D015415:Biomarkers; D013778:Tetrazolium Salts; C059087:2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-5-((phenylamino)carbonyl)-2H-tetrazolium hydroxide; D010088:Oxidoreductases