[The protective effects of intermedin 1-53 on oleic acid induced acute lung injury in rats].
OBJECTIVE
To investigate the effects of intermedin 1-53 on oleic acid induced acute lung injury (ALI) in rats and its possible mechanisms.


METHODS
Twenty-four male Wistar rats, weighting 280-300 g, were randomly divided into three groups (n = 8). In the oleic acid group, ALI was induced by injecting oleic acid (0.2 ml/kg) intravenously. In the intervention group, the rats received oleic acid as above, but intraperitoneal injection of intermedin 1-53 (2 nmol/kg in l ml saline) was given 1 h before and 2 h after oleic acid infusion, respectively. The control group was given normal saline (0.2 ml/kg). The animals were observed for 6 h after intravenous infusion. The histopathological changes of lung tissue were studied. The arterial blood gases, lung wet/dry weight ratio (W/D), leukocyte count and neutrophil differentials in bronchoalveolar lavage fluid (BALF) were measured. Contents of intermedin 1-53 in the plasma were detected with radioimmunoassay, myeloperoxidase activity, and malondialdehyde (MDA) and conjugated diene (C-diene) level of lung tissue were also measured.


RESULTS
The PaO(2) was higher and lung wet/dry weight ratio, leukocyte count and neutrophil counts in BALF were significantly lower in the intermedin group [(81.7 +/- 4.6) mm Hg (1 mm Hg = 0.133 kPa), 5.49 +/- 0.63, (57.9 +/- 7.4) x 10(4)/ml, 0.718 +/- 0.085, respectively] as compared to the oleic acid group [(60.8 +/- 3.2) mm Hg, 6.18 +/- 0.34, (122.0 +/- 16.6) x 10(4)/ml, 0.878 +/- 0.026], q value was 16.74, 3.43, 17.23, 6.32, respectively, all P < 0.05 or 0.01).


CONCLUSIONS
Intermedin 1 - 53 treatment significantly attenuated oleic acid-induced lung injury in rats. Intermedin 1-53 exerts pulmo-protective effects by inhibiting formation of lipid oxide products.
Yu
Xiao-min
XM
Department of Geriatric Medicine, Peking University First Hospital, Beijing 100034, China.
Liu
Xin-min
XM
Qi
Yong-fen
YF
Zhang
Zhi-gang
ZG
Tang
Chao-shu
CS
D055371:Acute Lung Injury / Q000139:chemically induced* / Q000378:metabolism*; D000818:Animals; D008168:Lung / Q000378:metabolism / Q000473:pathology; D008297:Male; D008315:Malondialdehyde / Q000378:metabolism; D019301:Oleic Acid / Q000009:adverse effects*; D009195:Peroxidase / Q000378:metabolism; D011763:Pyrrolizidine Alkaloids / Q000097:blood / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar
D011763:Pyrrolizidine Alkaloids; D019301:Oleic Acid; D008315:Malondialdehyde; D009195:Peroxidase; C018336:indicine