Overexpression of TGF-alpha increases lung tissue hysteresivity in transgenic mice. |
| |
Authors: | J J Pillow T R Korfhagen M Ikegami P D Sly |
| |
Institution: | TVW Telethon Institute for Child Health Research, West Perth 6872, WA, Australia. j.pillow@ich.ucl.ac.uk |
| |
Abstract: | Increased transforming growth factor (TGF)-alpha has been observed in neonatal chronic lung disease. Lungs of transgenic mice that overexpress TGF-alpha develop enlarged air spaces and pulmonary fibrosis compared with wild-type mice. We hypothesized that these pathological changes may alter the mechanical coupling of viscous and elastic forces within lung parenchyma. Respiratory impedance was measured in open-chested, tracheostomized adult wild-type and TGF-alpha mice by using the forced oscillation technique (0.25-19.63 Hz) delivered by flexiVent (Scireq, Montreal, PQ). Estimates of airway resistance (Raw), inertance (I), and the coefficients of tissue damping (G(L)) and tissue elastance (H(L)) were obtained by fitting a model to each impedance spectrum. Hysteresivity (eta) was calculated as G(L)/H(L). There was a significant increase in eta (P < 0.01) and a trend to a decrease in H(L) (P = 0.07) of TGF-alpha mice compared with the wild-type group. There was no significant change in Raw, I, or G(L). Structural abnormality present in the lungs of adult TGF-alpha mice alters viscoelastic coupling of the tissues, as evidenced by a change in eta. |
| |
Keywords: | |
|
| 点击此处可从《Journal of applied physiology (Bethesda, Md. : 1985)》浏览原始摘要信息 |
| 点击此处可从《Journal of applied physiology (Bethesda, Md. : 1985)》下载免费的PDF全文 |
|