Effect and mechanism of transient receptor potential canonical channel 3 on hyperoxic lung injury in neonatal rats.

The aim of this study is to research the expression of the transient receptor potential canonical channel 3 (TRPC3) in a neonatal hyperoxic lung injury model of bronchopulmonary dysplasia (BPD), and to further investigate the role of the TRPC3/nuclear factor-κB (NF-κB) signaling pathway in hyperoxia-induced BPD by a TRPC3 agonist (GSK1702934A). The hyperoxic lung injury model of BPD was established in Sprague-Dawley neonatal rats. Hematoxylin and eosin (HE) staining and radial alveolar count (RAC) values showed that the hyperoxic lung injury model of BPD was successfully established in the neonatal rats, and pulmonary edema was found in the neonatal rats with BPD. The results of reference transcriptome sequencing, Quantitative real-time PCR (qPCR), and western blot showed lower pulmonary expression of TRPC3 in the BPD group than in the control group. Immunofluorescence showed predominant expression of TRPC3 in airways and pulmonary vessels, and the fluorescence intensity of the BPD group was lower than that of the control group. Lung dry-to-wet weight ratio, HE staining, and RAC value showed that the lung histomorphology significantly improved in the BPD + TRPC3 agonist group compared with the BPD group on day 14 but did not revert to the level of the control group. According to qPCR results, compared with the control group, the expression of NF-κB1 decreased and the expression of NF-κBiz increased in the BPD group, whereas the expression of NF-κBiz decreased in the BPD + TRPC3 agonist group. Therefore, we draw the conclusion that TRPC3 may activate NF-κB by inhibiting NF-κBiz to promote cell proliferation and lung growth and development.