BACKGROUND: All organisms have developed an internal timing system capable of reacting to and anticipating environmental stimuli with a program of appropriately timed metabolic, physiologic and behavioral events. The alveolar epithelial type II cell of the mammalian lung synthesizes, stores, and secretes a lipoprotein pulmonary surfactant, which functions to stabilize alveoli at low lung volumes. METHODS: The authors investigated the diurnal variation of surfactant protein A, B and C mRNA accumulation. The diunal variation on gene expression of surfactant protein A, B and C was analysed using filter hybridization at 9 a.m., 4 p.m. and 11 p.m. Lung SP-A protein content was determined by double sandwich ELISA assay using a polyclonal antiserum raised in rabbits against purified rat SP-A. RESULTS: 1. The accumulation of SP-A mRNA at 4 p.m. was significantly decreased by 23.5% compared to the value at 9 a.m. (p < 0.05). 2. The accumulation of SP-B mRNA at 4 p.m. and 11 p.m. was decreased by 15.1% and 5.7%, respectively, compared to the value at 9 a.m. (p = 0.07, p = 0.69). 3. The accumulation of SP-C mRNA at 4 p.m. and 11 p.m. was decreased by 6.8% and 7.7%, respectively, compared to the value at 9 a.m. (p = 0.38, p = 0.57). 4. Total lung SP-A content at 4 p.m. and 11 p.m. was increased by 5.3% and 15.9%, respectively, compared to the value at 9 a.m. (p = 0.64, p = 0.47). CONCLUSION: These findings represent the diurnal variation of surfactant proteins mRNA expression in vivo. These results indicated that the diurnal variation of significant gene expression is observed in hydrophilic surfactant protein rather than in hydrophobic surfactant proteins.
BACKGROUND: All organisms have developed an internal timing system capable of reacting to and anticipating environmental stimuli with a program of appropriately timed metabolic, physiologic and behavioral events. The alveolar epithelial type II cell of the <span class="Species">mammalian lung synthesizes, stores, and secretes a lipoprotein pulmonary surfactant, which functions to stabilize alveoli at low lung volumes. METHODS: The authors investigated the diurnal variation of surfactant protein A, B and C mRNA accumulation. The diunal variation on gene expression of surfactant protein A, B and C was analysed using filter hybridization at 9 a.m., 4 p.m. and 11 p.m. Lung SP-A protein content was determined by double sandwich ELISA assay using a polyclonal antiserum raised in rabbits against purified ratSP-A. RESULTS: 1. The accumulation of SP-A mRNA at 4 p.m. was significantly decreased by 23.5% compared to the value at 9 a.m. (p < 0.05). 2. The accumulation of SP-B mRNA at 4 p.m. and 11 p.m. was decreased by 15.1% and 5.7%, respectively, compared to the value at 9 a.m. (p = 0.07, p = 0.69). 3. The accumulation of SP-C mRNA at 4 p.m. and 11 p.m. was decreased by 6.8% and 7.7%, respectively, compared to the value at 9 a.m. (p = 0.38, p = 0.57). 4. Total lung SP-A content at 4 p.m. and 11 p.m. was increased by 5.3% and 15.9%, respectively, compared to the value at 9 a.m. (p = 0.64, p = 0.47). CONCLUSION: These findings represent the diurnal variation of surfactant proteins mRNA expression in vivo. These results indicated that the diurnal variation of significant gene expression is observed in hydrophilic surfactant protein rather than in hydrophobic surfactant proteins.
Authors: P K Smith; R I Krohn; G T Hermanson; A K Mallia; F H Gartner; M D Provenzano; E K Fujimoto; N M Goeke; B J Olson; D C Klenk Journal: Anal Biochem Date: 1985-10 Impact factor: 3.365
Authors: Mark S Dooner; Connor Stewart; Yanhui Deng; Elaine Papa; Mandy Pereira; Michael Del Tatto; Shannon Johnson; Sicheng Wen; Ashley Amaral; Jason Aliotta; Peter J Quesenberry; Laura R Goldberg Journal: PLoS One Date: 2018-11-26 Impact factor: 3.240
Authors: Isaac K Sundar; Hongwei Yao; Yadi Huang; Elizabeth Lyda; Patricia J Sime; Michael T Sellix; Irfan Rahman Journal: PLoS One Date: 2014-02-10 Impact factor: 3.240