Protective effect of urinary trypsin inhibitor on myocardial mitochondria during hemorrhagic shock and reperfusion.
OBJECTIVE
To examine the mitochondrial function in the myocardium after hemorrhagic shock and reperfusion and to evaluate the protective effect of urinary trypsin inhibitor (UTI) on mitochondria.


METHODS
Animal experiment.


METHODS
University research laboratory.


METHODS
Wistar rats receiving 50,000 units/kg/hr of UTI (n = 27; UTI group) and control rats (n = 26; control group).


METHODS
Rats were subjected to low-perfusion ischemia with the left ventricular systolic pressure maintained at 50 mm Hg for 60 mins by bleeding, followed by a 60-min reperfusion by transfusion of shed blood. UTI was infused continuously from 10 mins before bleeding. Cardiac function was measured before bleeding, after bleeding, and after transfusion; at each determination point, the myocardial contents of adenosine triphosphate (ATP), creatine phosphate (P-Cr), pyruvate (Pyr), and lactate (Lac) were measured enzymatically. The cytosolic phosphorylation potential (PP) as well as the redox potential of the oxidized form of nicotinamide adenine dinucleotide/reduced form of nicotinamide adenine dinucleotide couple in mitochondria (Eh(NAD+/NADH)) and change of Gibbs free energy in ATP hydrolysis (deltaG(ATP hydrolysis) energy) were calculated.


RESULTS
Cardiac function decreased during hemorrhagic shock but improved significantly in the UTI group after transfusion compared with the control group. Lac and the Lac/Pyr ratio were significantly lower in the UTI group than in the control group after transfusion. ATP and P-Cr were significantly higher in the UTI group than in the control group after transfusion. PP (x10(3) M-1), Eh(NAD+/NADH) (x - 1 mV), and deltaG(ATP hydrolysis) (x - 1 kcal/mol) were 1.9 +/- 0.4, 266 +/- 4, and 9.7 +/- 0.2, respectively, in the control group and 4.0 +/- 0.9, 274 +/- 5 and 13.0 +/- 0.2, respectively, in the UTI group after transfusion (p <.001, p <.001, and p <.001, respectively).


CONCLUSIONS
In reperfusion after hemorrhagic shock, oxidative phosphorylation in myocardial mitochondria is impaired and energy production remains reduced, even after reperfusion. UTI contributed to the recovery of cardiac function after reperfusion, probably by reducing the severity of mitochondrial dysfunction during a state of shock and by maintaining energy production.
Masuda
Takashi
T
Department of Rehabilitation, School of Allied Helath Sciences, Kitasato University, Sagamihara, Kanagawa, Japan. tak9999@med.kitasato-u.ac.jp
Sato
Kiyotaka
K
Noda
Chiharu
C
Ikeda
Kazuko M
KM
Matsunaga
Atsuhiko
A
Ogura
Misao N
MN
Shimizu
Kazuhiko
K
Nagasawa
Hiroshi
H
Matsuyama
Narihisa
N
Izumi
Tohru
T
D000255:Adenosine Triphosphate / Q000378:metabolism; D000818:Animals; D001794:Blood Pressure / Q000502:physiology; D001804:Blood Transfusion, Autologous; D004734:Energy Metabolism / Q000502:physiology; D006023:Glycoproteins / Q000494:pharmacology*; D006339:Heart Rate / Q000502:physiology; D019344:Lactic Acid / Q000378:metabolism; D008297:Male; D008929:Mitochondria, Heart / Q000187:drug effects* / Q000502:physiology; D028361:Mitochondrial Diseases / Q000503:physiopathology; D015428:Myocardial Reperfusion Injury / Q000503:physiopathology*; D010084:Oxidation-Reduction; D010725:Phosphocreatine / Q000378:metabolism; D019289:Pyruvic Acid / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D012771:Shock, Hemorrhagic / Q000503:physiopathology*; D013318:Stroke Volume / Q000502:physiology
D006023:Glycoproteins; D010725:Phosphocreatine; D019344:Lactic Acid; D019289:Pyruvic Acid; D000255:Adenosine Triphosphate; C028665:urinastatin