Angelica On Acute Hypoxic Pulmonary Hypertension

In this study, we investigated the effects of extract of Angelica sinensis(danggui) on acute hypoxic pulmonary hypertension in ten anaesthelized dogs. Thermodilution balloon tipped catheter was inserted into pulmonary artery via right jugular vein to monitor hemodynamic changes. The animals were intubated and ventilated mechanically with ventilators. Every episode of hypoxic ventilation lasted for 10 minutes (FiO₂=10%), after that, PaO₂ and SaO₂ decreased significantly from 107.7 ± 12.1 mmHg to 47.7 ± 5.5 mmHg and 96.8 ± 1.3% to 80.0± 7.3% respectively, while pH and PaCO₂ had no obvious change. When ventilated with 21% O₂ , PVR were 15.0± 4.0 mmHg and 5.6 ± 2.7 dynes.sec.cm^-5 respectively. In case of hypoxia, PAPm was 24.6 ± 4.2mmHg ( increased 8.6 ± 4.0 mmHg, P< 0.01 ), PVR was 9.4± 4.0 dynes.sec.cm^-5 (increased 3.8 ±1.9 dynes.sec.cm^-5,P<0.01). Hypoxia had no significant effect on HR, CO, RAP, PCWP, BPm, SVR. Danggui did not change the hemodynamics when ventilated with 21%O₂. Within Half an hour of intravenous injection (via right atrium ) of danggui (total dose 0.75g / Kgwt), the increment of PAPm and PVR due to hypoxia were inhibited significantly(P<0.01).The plasma levels of TXB₂ and 6-Keto-PGF_1α were measured by radioimmnue assay in 5 dogs. 6-Keto-PGF_1α had no remarkable change before and after hypoxia while TXB₂ increased significantly (P<0.01). The levels of TXB₂ and 6-Keto—PGF_1α during hypoxic state did not change before and after danggui injection, however the TXB₂/6-Keto-PGF_1α ratio...