[Animal Modeling]-Changes and Significance of Arterial Blood Gas Analysis Indexes 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 36 SD male rats were randomly divided into normoxia control group and hypoxia (1, 3, 7, 14 and 21 d) groups. The hypoxia group was placed in a hypoxia chamber (O2 volume fraction of 10%). The number of days. The right ventricular systolic pressure (RVSP) was measured by the right heart catheterization method, and the mass ratio of the right ventricle (RV) to the left ventricle (LV) + ventricular septum (S) was calculated to obtain the right ventricular hypertrophy index (RVHI). Masson staining method was used to observe the pathological changes of pulmonary artery. Take blood from the abdominal aorta for arterial blood gas analysis. The measurement indicators include pH, arterial partial pressure of carbon dioxide (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 rats in each hypoxic group were significantly higher than those of the normoxic control group (P<0.05). Compared with the normoxic control group, the pulmonary arteries of rats in the hypoxia (7, 14, 21 d) group were abnormally remodeled. Compared with the normoxic control group, the pH and HCO3- content of each hypoxic group were significantly reduced (P<0.05), PaCO in the hypoxic 21d group was significantly increased (P<0.05), and the PaO2 and SaO2 of the hypoxic 14d group were both significantly Decrease (P <0.05), the Na+ concentration of each group except hypoxia for 1 day and the Ca2+ concentration of hypoxia 3d group were significantly reduced (P<0.05), and the K+ concentration of each group was significantly increased except for hypoxia 14d (P<0.05) , Hct and Hb levels in each hypoxic group were significantly increased (P<0.05). In the arterial blood gas analysis of hypoxic pulmonary hypertension rats, Nat level was negatively correlated with RVSP (P<0.05).

  Conclusion The arterial blood gas analysis indexes pH, PaCO2, PaO2, SaO2, HCO3-, Na+, K+, Ca2+, Hct and Hb of rats with hypoxic pulmonary hypertension change significantly, and they participate in and regulate the occurrence and development of hypoxic pulmonary hypertension. Among them, Na+ The level may be an indirect indicator of the severity of hypoxic pulmonary hypertension.