Suprachiasmatic lesions eliminate 24-h blood pressure variability in rats.
To evaluate whether the suprachiasmatic nuclei (SCN) control 24-h rhythmicity in cardiovascular function, rats were subjected to computerized recording of 24-h blood pressure (BP) and heart rate (HR) following SCN lesions. In sham- and nonlesioned rats, circadian patterns of BP and HR ran in phase with those in feeding behavior. In SCN-lesioned rats circadian rhythmicity in BP, HR and food intake were abolished. Minute-to-minute variation of BP and HR was similar as in sham- and nonlesioned rats. We conclude that long-term but not short-term variability of blood pressure and heart rate is largely determined by SCN-controlled activity levels.
Janssen
B J
BJ
Department of Pharmacology, University of Limburg, Maastricht, The Netherlands.
Tyssen
C M
CM
Duindam
H
H
Rietveld
W J
WJ
D000818:Animals; D001794:Blood Pressure / Q000502:physiology*; D002940:Circadian Rhythm / Q000502:physiology*; D004435:Eating / Q000502:physiology; D006439:Hemodynamics / Q000502:physiology; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D013493:Suprachiasmatic Nucleus / Q000033:anatomy & histology / Q000502:physiology*