Protective mechanism of ultrafiltration against cardiopulmonary bypass-induced lung injury.
BACKGROUND
We previously demonstrated a negative effect of cardiopulmonary bypass (CPB) in a canine model of single-lung graft function and an improved effect with ultrafiltration during CPB.


OBJECTIVE
To investigate the mechanism of these effects, focusing on cytokines and pulmonary surfactants using real-time quantitative reverse transcriptase-polymerase chain reaction (RT-PCR).


METHODS
Fifteen left-sided single-lung transplant procedures were performed in pairs of dogs. The animals were divided into 3 groups. In one group, transplantation was performed without CPB (non-CPB group); in a second group, transplantation was performed with CPB and CPB flow was decreased slowly and pulmonary artery pressure was controlled (CPB group; and in the third group, transplantation was performed with CPB and ultrafiltration (CPB+UF group). Grafted lung specimens were harvested for RT-PCR of cytokines (IL-6, IL-8, and IL-10) and surfactant proteins (SP-A, SP-B, and SP-C).


RESULTS
Real-time quantitative RT-PCR demonstrated increased IL-6 expression in the CPB group compared with the non-CPB group. IL-6 gene expression was suppressed and pulmonary surfactant restored using ultrafiltration. Gene expression of surfactant protein (SP)-A, SP-B, and SP-C was decreased in the CPB group compared with normal lung and ultrafiltration groups, which demonstrated sustained gene expression of SP-A and SP-B.


CONCLUSIONS
Cardiopulmonary bypass has negative effects on grafts; however, ultrafiltration attenuates acute lung dysfunction by decreasing the inflammatory response and increasing pulmonary surfactant.
Koike
T
T
Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan.
Tsuchida
M
M
Saitoh
M
M
Haga
M
M
Satoh
K
K
Aoki
T
T
Toyabe
S-I
SI
Hayashi
J I
JI
D000818:Animals; D002315:Cardiopulmonary Bypass / Q000009:adverse effects / Q000379:methods*; D037222:Collectins / Q000235:genetics; D016207:Cytokines / Q000235:genetics; D017931:DNA Primers; D004285:Dogs; D008168:Lung / Q000502:physiology; D055370:Lung Injury / Q000209:etiology* / Q000517:prevention & control*; D016040:Lung Transplantation / Q000379:methods*; D023421:Models, Animal; D011663:Pulmonary Surfactants / Q000032:analysis; D012333:RNA, Messenger / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014462:Ultrafiltration / Q000379:methods*
D037222:Collectins; D016207:Cytokines; D017931:DNA Primers; D011663:Pulmonary Surfactants; D012333:RNA, Messenger