Mechanism For 5-HT On Monocrotaline-induced Pulmonary Hypertension And Peucedanum Praeruptorum Dunnon Inhibited Pulmonary Arterial Hypertension

Objectivepulmonary artery hypertension (PHT) is one of the commonly encountered diseases. Both the morbidity and mortality are rather high. The pathological changes of pulmonary artery hypertension compromise two essential changes, i. e. pulmonary vasoconstriction and pulmonary vasoconstruction. Peucedanum praeruptorum Dunnon ( PPD ) has been found to have abroad spectrum of pharmacolohical actions . It can pass to Ca2 + channel 's anti - Function with to K + channel's open function to vasodilator pulmonary vessel, and lower pulmonary artery pressure. Increased contractile of pulmonary vessel associates with excessive Ca2 + in smooth muscle cell. Calcium act the second message during the process of pulmonary vasoconstriction and pulmonary vasoconstriction. The channel antagonists of calcium inhibit calcium channel, reducing the Ca2 + intrafluiding or preventing calcium from cell. The channel antagonists of calcium inhibit pulmonary vasoconstriction and pulmonary vasoconstriction.5 - HT is a potent pulmonary vasoconstrictor. Pulmonary vasoconstriction to 5 - HT is mediated by the 5 - HT receptor. In normal human pulmonary circulation, the 5 - HT1B/1Dreceptor mediates pul-monary vasoconstriction. In normal rats, pulmonary vasoconstriction to 5 - HT is mediated predominantly by the 5 - HT2A receptor. However, in hypoxic pulmonary hypertension rats, 5 - HT - induced vasoconstriction is mediated by both the 5 - HT1Band 5 - HT2A receptor. 5 -HT, 5 - HT receptor play an important role during the pathologic changes of pulmonary artery hypertension, but it is not clear whether PPD has an effect against pulmonary vascular to 5 - HT contractile responses during PHT.Experiment materials and methodWistar rats ( 60 , weighing 140 - 160g) were devided into 5 groups; control, MCT, MCT + PPD vehicle and MCT + PPD (50, 100mg kg - d -1 , ig. MGT was dissolved in distilled water. It was injected , 60 mg kg -1. On day 0, rats were injected MCT. PPD was given 3 hours after ip. MCT for 21 days. Then, Hemodynamic, right heart index, blood gas analysis and pulmonary arteries to 5 - HT responses were measured.ResultMonocrotaline - induced rats have been increased the right heart index, PHT and to 5 - HT contractile responses, however, decreased PaO2 PPD decreased the right heart index, PHT and to 5 - HT contractile responses in Monocrotaline - induced rats. PPD increased PaO2 in Monocrotaline - induced rats.Conclusions1. Monocrotaline - induced rats have increased the right heart index, PHT and to 5 - HT contractile responses however, decreased PaO2.2. PPD decreased the right heart index, PHT and increased PaO2.3. PPD induced 5 - HT contractile responses in Monocrotaline -induced rats.4. Monocrotaline - induced rats of PHT might associate with 5 -HT; PHT which prevented by PPD might effect mechanism of 5 - HT.