OBJECTIVETo study the myocardial protection on septic rats by Tongguan Capsule (TC).

METHODSTotally 120 SD rats were used to prepare the septic rat model using cecal, ligation and puncture (CLP). After modeling they were divided into three groups, i.e., the sham-operation group, the model group, the treatment group (treated by TC), 40 in each group. Each group was further divided into 5 subgroups according to different time points, i.e., 12 h, 24 h, 48 h, 72 h, and 7 days after CLP, 8 in each subgroup. CLP was performed in rats of the model group and the treatment group. The abdominal cavity of rats in the sham-operation group was opened. The incision of the abdominal wall was then sutured after their cecum was slightly flipped without puncture. Normal saline (at the daily dose of 10 mL/kg) was given by gastrogavage to rats in the model group and the sham-operation group. TC (at the daily dose of 600 mg/kg) was given to rats in the treatment group by gastrogavage, once daily, for 7 successive days. The hemodynamic changes such as left ventricular systolic pressure (LVSP), left ventricular pressure maximal rate of fall (- dp/dtmax), left ventricular pressure maximal rate of rise ( +dp/dtmax), inflammatory factors [such as tumor necrosis factor-alpha (TNF-alpha) and, IL-6, troponin I (CTn I )] were observed in all groups at each time point. The morphological changes of myocardial cells were observed under light and electron microscope 3 days later.

RESULTSCompared with the sham-operation group, the LVSP and +dp/dtmax decreased, and -dp/dtmax, CTn I , TNF-alpha, and IL-6 increased 24 -72 h after surgery in the model group, showing statistical difference (P<0.01). Compared with the model group, the LVSP and +dp/dtmax increased, and -dp/dtmax, CTn I , TNF-alpha, and IL-6 decreased 24 -72 h after surgery in the treatment group, showing statistical difference (P<0.05, P<0.01). Images under light microscope showed granular degeneration of myocardial cells could be occasionally seen in the treatment group. The transverse striation of myocardial cells was quite clear. The coronary artery was dilated and congested, with mild inflammation of interstitium. Images under electron microscope showed that the nucleus of myocardial cells was complete with quite clear Z-line in the treatment group. The number of the mitochondria increased. The mitochondria was swollen, but with more clear structure of cristae and mild fibrosis of interstitium.

CONCLUSIONTC could improve the depression state of myocardial cells of septic rats, thus improving the prognosis of sepsis.