[The effect of compound macrostem onion capsule on metabolism of arachidonic acid in a rat model of monocrotaline-induced pulmonary artery hypertension].

OBJECTIVE

To study the effect of compound macrostem onion capsule (CMOC) on products of arachidonic acid metabolism in monocrotaline (MCT)-induced pulmonary artery hypertension rats.

METHODS

Sixty SD rats were divided into a control group, a model group, and three experimental groups in which the rats were fed with captopril, small dose single dosage, and large dose (double dosage) of CMOC, respectively. The rat model was made by MCT peritoneal injection. The mean pulmonary arterial pressure (mPAP) and the mean right ventricular pressure (mRVP) were measured. Thromboxane B(2) (TXB(2)) and 6-keto-prostaglandin Fia (6-K-PGFia) were determined by RIA method.

RESULTS

The mPAP in rats of the model group [(36.9 +/- 4.8) mm Hg, 1 mm Hg = 0.133 kPa] was significantly higher than that of the control group [(16.4 +/- 2.1) mm Hg, all P < 0.01]. The mPAP in rats of the double dosage and single dosage of CMOC groups were (26.2 +/- 2.8) mm Hg and (27.9 +/- 2.8) mm Hg, respectively; both were significantly lower than those of the model group (all P < 0.01). TXB(2) in rats of the model group was significantly higher than that of the control group (P < 0.05), while 6-K-PGFia in the model group was significantly lower than that of the control group (P < 0.01). TXB(2) in rats of the double dosage CMOC group was significantly lower than that of the model group, but 6-K-PGFia in rats of the CMOC groups was significantly higher than that of the model group (P < 0.05, < 0.01).

CONCLUSION

CMOC is effective in reducing pulmonary artery hypertension. Inhibition of TXB(2) and augmentation of 6-K-PGFia might be the underlying mechanisms.