PURPOSE: To study the mechanism of pulmonary edema after seawater drowning (PE-SWD),the rat model of PE-SWD was developed and observed the histopathological changes, the ultrastructure changes, the changes of expressions of KGF and KGFR.
METHODS: Twenty-four male Sprague-Dawley rats were randomized into 3 groups: (1) Control group, (2) Drowning group, and (3) Oleic acid group. The infiltrated polymorphonuclear (PMN) leukocytes were calculated. Ultrastructural changes of lungs were observed by electronic microscopy. The wet / dry ratio (W/D) of the lung were calculated. Expressions of KGF and KGFR were assayed under fluorescence microscope. With RT-PCR the expression of the mRNA of KGF and KGFR was assayed. The component of BALF was analyzed.
RESULTS: The pulmonary pathologic changes showed diffuse hyperemia and edema in drowning group and oleic acid group. Hyperemia and edema were seen in bronchial submucous layer with inflammatory cell infiltration most of which were neutrophils. The PMN under high power fields in both drowning group and oleic acid group were higher than in the control group(P< 0.05). In drowning group and oleic acid group, vacuolation occurred in lamellar body of AEC. The lattice and other types of tubular myelin exfoliated into the alveolar cavity. The PS layer was rough and was broken in some areas, or disappeared. The expression of KGF and KGFR both in drowning group and oleic acid group were positive and those in control group were negative. There was much more increased expression of KGF and KGFR mRNA in the drowning group than in the oleic acid, both of them more than the control group.
CONCLUSION: An appropriate working animal model with PE-SWD was established. Histopathological and ultrastructural change in drowning group is more severe than oleic acid group. Expressions of KGF and KGFR are increased in drowning group and oleic acid group.
CLINICAL IMPLICATIONS: this study adds sea-induced lung injury new mechanism and present new treatment management.
DISCLOSURE: Guifang Wang, No Financial Disclosure Information; No Product/Research Disclosure Information