Calcium Sensing Receptor Intervention Of Persistent Pulmonary Hypertension Model Ca²⁺ Concentration Measurement In Smooth Muscle Cells In Mice

Objective:The calcium sensitive receptor（calcium-sensing receptor,CaSR）was treated on the basis of persistent pulmonary hypertension（PPH）in C57BL/6 newborn mice induced by persistent hypoxia at normal pressure.The changes of calcium fluorescence intensity in pulmonary artery smooth muscle cells of newborn mice were detected by real-time laser confocal technique.Methods:SPF without the cage of C57BL/6 mice 75 mice in female and male rats 1:2 paired,pregnant female rats,1 female+6 rats,newborn total 96 rats were randomly divided into control group,PPH group,PPH+group,PPH+inhibitor group agonist the 24（mother rats and rats without cage）.The PPH mouse model was induced by 12%oxygen concentration,and the newborn mice CaSR agonist（Gd Cl₃）and CaSR inhibitor（NPS2390）were given daily intraperitoneal injection,and the duration of the model was 14 days.After the completion of the model,the pulmonary artery of four groups of newborn mice was stripped under the aseptic environment.The primary culture of pulmonary artery smooth muscle cells（PASMCs）was performed in vitro.The pulmonary artery smooth muscle cells were separated by differential centrifugation.The pulmonary artery smooth muscle cells were determined by immunofluorescence,and the pulmonary activity of the 4 new mice was treated with the calcium ion indicator Fluo-3/AM.Vascular smooth muscle cells were incubated under load.The fluorescence intensity of calcium in 4 groups of PASMCs was continuously detected by confocal laser scanning microscope.Results:Compared with the control group,the thickness of the small blood vessel wall of the PPH group increased with the ratio of the outer diameter of the vessel and the ratio of the right ventricular/left ventricular thickness,the ratio was[（21.1%+4.86%）ratio（26.6%+2.48%）,（0.62+0.003）ratio（0.83+0.12）),and the difference was statistically significant（P<0.05）,indicating that the new PPH mouse model was constructed successfully.The median of fluorescence intensity of calcium ion in PASMCs in control group,PPH group,PPH+agonist group and PPH+inhibitor group were 108.60（106.63,110.50）、2183.80（2087.63,2247.40）、2187.25（2092.33,2257.75）、1118.85（1106.33,1134.00）PPH group,PPH+agonist group and PPH+suppressor group were all higher than those of the control group.The PPH group was higher than the group of the inhibitor+inhibitor.The difference was statistically significant.There was no significant difference in learning meaning（P<0.05）between PPH group and PPH+agonist group（P>0.05）.Conclusion:CaSR may be involved in the occurrence and development of PPH in newborn mice induced by hypoxia by influencing the concentration of calcium ion in the pulmonary artery smooth muscle cells.