Updated project metadata. To understand the molecular change occurring in the atria during obstructive sleep apnea, we have implemented a rat model of OSA involving the surgical implantation of a tracheal obstructive device, allowing the rats to remain conscious and free-roaming throughout 2 weeks of apnea administration. Rats were divided into severe and moderate apnea groups, receiving a 23 second or 13 second apneas per minute, respectively. The two-dimensional polyacrylamide gel electrophoresis (2D PAGE) of atrial homogenates to compare the dysregulations in the protein pattern in severe and moderate apnea when compared to control.