【Animal Modeling】-Changes and Significance of Arterial Blood Gas Analysis in Rats with Chronic Hypoxic Pulmonary Hypertension

  Objective To investigate the changes and significance of arterial blood gas analysis indexes in a rat model of hypoxic pulmonary hypertension induced by chronic hypoxia.

  Methods Thirty-six SD male rats were randomly divided into normoxia control group and hypoxia (1, 3, 7, 14 and 21 d) groups. days. Right ventricular systolic blood pressure (RVSP) was measured by right heart catheterization, and the mass ratio of right ventricle (RV) to left ventricle (LV) + interventricular septum (S) was calculated to obtain right ventricular hypertrophy index (RVHI). The pathological changes of pulmonary artery were observed by Masson staining. Blood was taken from the abdominal aorta for arterial blood gas analysis, and the measured indicators included pH, arterial carbon dioxide partial pressure (PaCO2), arterial oxygen partial pressure (PaO2), arterial oxygen saturation (SaO2), bicarbonate ( HCO3-), sodium ion (Na+), potassium ion (K+), calcium ion (Ca2+), hematocrit (Hct) and hemoglobin (Hb).

  Results The RVSP and RVHI of the hypoxic groups were significantly higher than those of the normoxia control group (P<0.05). Compared with the normoxic control group, the pulmonary artery of the rats in the hypoxic (7, 14, 21 d) group was abnormally remodeled. Compared with the normoxia control group, the pH and HCO3- contents in each hypoxia group were significantly decreased (P<0.05), the PaCO in the hypoxia group for 21 days was significantly increased (P<0.05), and the PaO2 and SaO2 in the hypoxia group for 14 days were significantly increased (P<0.05). (P < 0.05), the Na+ concentration in each group except hypoxia for 1 day and the Ca2+ concentration in hypoxia group for 3 days were significantly decreased (P < 0.05), and the K+ concentration was significantly increased in each group except for 14 days of hypoxia (P < 0.05). , the levels of Hct and Hb in each hypoxia group were significantly increased (P<0.05). The level of Nat in arterial blood gas analysis of hypoxic pulmonary hypertension rats was negatively correlated with RVSP (P<0.05).

  Conclusion The arterial blood gas analysis indexes of pH, PaCO2, PaO2, SaO2, HCO3-, Na+, K+, Ca2+, Hct and Hb in hypoxic pulmonary hypertension rats have significant changes, which are involved in and regulate the occurrence and development of hypoxic pulmonary hypertension. Among them, Na+ Levels may be an indicator of indirect assessment of the severity of hypoxic pulmonary hypertension.