To evaluate the
therapeutic effects and mechanisms of
tetramethylpyrazine (
TMP), a Chinese herbal medicine, on the
lung injury in bile-induced acute haemorrhagic necrotizing
pancreatitis (AHNP) in the SD rats, the rats were randomly divided into three groups:
sham-operative, untreated and
TMP treated. AHNP model were induced by
ligation with 5%
taurocholate. The changes of lung index, serum
lipid peroxide (LPO), TXB2,
6-keto-PGF1 alpha, and lung pathology at light and electron microscope were all investigated at 1, 6, 12 hours after induction of AHNP model. Survival rate of AHNP in rats were recorded also. Results of the study showed that in untreated group, the time-related progressive pancreatic haemorrhage and
necrosis, accompanied by
pancreatitis-associated
lung injury, such as pronounced pulmonary congestion, alveolar and interstitial
edema, polymorphonuclear granulocytes infiltration, transparent membrane formation, the density of layer body in type II endothelial cells decreasing, with some vacuole formation, mitochondria, endoplasmic reticulum swollen, basal membrane of endothelial cells
rupture were observed. The level of LPO elevated at 1 hour after induction of AHNP and peaked at 12 hours. TXB2 and
6-keto-PGF1 alpha was increased. Using
TMP treatment, survival rate increased, and lung at light and electron microscope were much improved and lung index, value of LPO, TXB2 decreased significantly,
6-keto-PGF1 alpha increased slightly, the ratio of TXB2/
6-keto-PGF1 alpha was stabilized. It was suggested that
TMP has definite
therapeutic effects on AHNP-related
lung injury in rats, and exerted by scavenging
oxygen free radical, inhibiting synthesis of TXA2, augmenting production of PGI2 and maintaining balance between TXA2 and PGI2.