Arterial Pressure and Heart Rate Increase during REM Sleep in Adenosine A2A-Receptor Knockout Mice, but not in Wild-Type Mice

Rapid eye movement (REM)-sleep related changes in arterial pressure (AP) and heart rate (HR) were observed in homozygous and heterozygous adenosine A2A receptor (A2AR) knockout (KO) mice, and the corresponding wild-type mice. During REM sleep, the mean AP (MAP) and HR were clearly increased in the homozygous A2AR KO mice, while, in the wild-type mice, they were decreased or maintained at the same level. Neither homozygous nor heterozygous A2AR KO mice showed significant difference in diurnal pattern and the hourly values of MAP and HR compared to the wild-type mice. From these findings, it is likely that the adenosine A2AR is involved in autonomic regulation during REM sleep.