Arterial stiffness and the autonomic nervous system during the development of Zucker diabetic fatty rats.
OBJECTIVE
This study aimed to investigate the role played by sympathovagal balance in arterial stiffness, a common feature of insulin resistance and type 2 diabetes.


METHODS
We investigated the relationship between autonomic nervous system activity and arterial stiffness in Zucker diabetic fatty rats (ZDF: Gmi-fa/fa) and their age-matched controls (lean: ?/fa). Using simultaneous catheterization of the proximal and distal aorta, we measured intra-arterial blood pressure (BP), heart rate (HR), their variability (spectral analysis) and aortic pulse wave velocity (PWV) in a series of at least six conscious rats aged 6, 12, 18 and 24 weeks.


RESULTS
BP and PWV increased with age (P<0.001) in both strains with no differences between strains, despite the insulin resistance already present at 6 weeks in ZDF rats. HR was significantly lower (P<0.001) in ZDF than in lean rats. In ZDF compared with lean rats, the low-frequency (LF) component of the systolic BP variations and the LF/high-frequency (HF) component of the pulse interval (PI) variation ratio were reduced (P<0.01 and P<0.05, respectively), while the HF component of the PI (HF-PI) variation was raised (P<0.05). PWV was negatively correlated with HF-PI (r=-0.37, P<0.01), but not with biochemical parameters. HF-PI was an independent variable explaining the variation in PWV.


CONCLUSIONS
During the development of disease of ZDF rats, sympathovagal balance might account for the lack of increase in PWV.
Cosson
E
E
Inserm, EMI-U0107, Paris, France. emmanuel.cosson@jvr.aphp.fr
Valensi
P
P
Laude
D
D
Mesangeau
D
D
Dabire
H
H
D000375:Aging; D000818:Animals; D001158:Arteries / Q000503:physiopathology*; D050197:Atherosclerosis / Q000209:etiology / Q000503:physiopathology*; D001341:Autonomic Nervous System / Q000503:physiopathology*; D003924:Diabetes Mellitus, Type 2 / Q000150:complications / Q000503:physiopathology*; D004195:Disease Models, Animal; D018450:Disease Progression; D004548:Elasticity; D005583:Fourier Analysis; D006439:Hemodynamics; D008297:Male; D018670:Monitoring, Ambulatory; D051381:Rats; D011924:Rats, Zucker; D013223:Statistics as Topic; D014630:Vagus Nerve / Q000502:physiology