Influenza A(H1N1)pdm09 virus aggravates pathology of blood vessels in
Wistar rats with premorbid acute cardiomyopathy
Abstract
Influenza virus can infect vascular endothelium and cause endothelial
dysfunction. Persons at higher risk for severe influenza are patients
with acute and chronic cardiovascular disorders; however, the mechanism
of influenza-induced cardiovascular system alteration remains not fully
understood. Thirty Wistar rats were divided in six groups – four
experimental and two control. Rats from each experimental group were
treated with doxorubicin following echocardiography confirmation of
acute cardiotoxicity. Two groups of rats were intranasally inoculated
with rat-adapted influenza A(H1N1)pdm09 virus, while two other groups –
with α-MEM. After 24 and 96 hours mesenteric vessels were harvested for
studying vasomotor activity using wire myograph and endothelial factors
(eNOS, PAI-1 and tPA) expression by immunohistochemistry; PAI-1 and tPA
concentration was analyzed in blood plasma by ELISA. Significant
decrease in maximal response of mesenteric arteries of infected rats
with premorbid acute cardiomyopathy to both vasoconstrictor and
vasodilator at 24 and 96 hpi was registered compared to uninfected rats
with acute cardiomyopathy and control rats. Expression of eNOS in
mesenteric vascular endothelium was modulated at 24 and 96 hpi. PAI-1
expression was increased by 3.47-fold at 96 hpi, while concentration of
PAI-1 in the blood plasma was increased by 6.43-fold at 24 hpi compared
with uninfected rats with acute cardiomyopathy. tPA concentration in
plasma was also modulated at 24 hpi and 96 hpi compared with uninfected
rats with acute cardiomyopathy. The obtained data indicate that
influenza A(H1N1)pdm09 virus in rats aggravates the course of premorbid
acute cardiomyopathy causing a pronounced dysregulation of endothelial
factors expression and vasomotor activity impairment of mesenteric
arteries.