AJP - Heart and Circulatory Physiology, Vol 270, Issue 2 575-H582, Copyright © 1996 by American Physiological Society

ARTICLES

Auto- and cross-spectral analysis of cardiovascular fluctuations during pentobarbital anesthesia in the rat

C. C. Yang, T. B. Kuo and S. H. Chan
Center for Neuroscience, National Yang-Ming University, Taipei, Taiwan, Republic of China.

We applied auto- and cross-spectral analysis of systemic arterial pressure (SAP) and heart rate (HR) signals to quantify the effects of pentobarbital sodium on short-term cardiovascular fluctuations in adult, male Sprague-Dawley rats. Intravenous administration of pentobarbital, delivered as a bolus injection (5, 10, or 20 mg/kg) or continuous infusion (10, 20, or 40 mg.kg-1.h-1), elicited only mild hypotension and tachycardia. This was accompanied by a dose-related depression of the very low (0-0.25 Hz) and low (0.25-0.8 Hz)-frequency components of both SAP and HR signals and high (0.8-2.4 Hz)-frequency component of HR signals. Cross-spectral analysis of SAP and HR signals during intravenous infusion of pentobarbital revealed a maintained coherence in the high-frequency range, together with a gradual and dose-related decrease in magnitude of transfer function and baro-receptor reflex sensitivity. Stable plasma concentration and all hemodynamic parameters were observed during 120 min of infusion at 20 mg.kg-1.h-1. Under this dosing condition, autonomic blockade by phentolamine, propranolol, or atropine still evoked discernible but differential reductions in the SAP and HR spectral components. Our data suggest that continuous intravenous administration of pentobarbital at 20 mg.kg-1.h-1 offers maintained anesthesia while preserving the capacity of cardiovascular regulation.

This article has been cited by other articles:

				L.-F. Zhang, J.-H. Cheng, X. Liu, S. Wang, Y. Liu, H.-B. Lu, and J. Ma Cardiovascular changes of conscious rats after simulated microgravity with and without daily -Gx gravitation J Appl Physiol, October 1, 2008; 105(4): 1134 - 1145. [Abstract] [Full Text] [PDF]

				S. Rey, M. P. Tarvainen, P. A. Karjalainen, and R. Iturriaga Dynamic time-varying analysis of heart rate and blood pressure variability in cats exposed to short-term chronic intermittent hypoxia Am J Physiol Regulatory Integrative Comp Physiol, July 1, 2008; 295(1): R28 - R37. [Abstract] [Full Text] [PDF]

				C. J. Lai, C. C. H. Yang, Y. Y. Hsu, Y. N. Lin, and T. B. J. Kuo Enhanced sympathetic outflow and decreased baroreflex sensitivity are associated with intermittent hypoxia-induced systemic hypertension in conscious rats J Appl Physiol, June 1, 2006; 100(6): 1974 - 1982. [Abstract] [Full Text] [PDF]

				T. B. J. Kuo, C. J. Lai, F.-Z. Shaw, C.-W. Lai, and C. C. H. Yang Sleep-related sympathovagal imbalance in SHR Am J Physiol Heart Circ Physiol, March 1, 2004; 286(3): H1170 - H1176. [Abstract] [Full Text] [PDF]

				S. H. H. Chan, K.-F. Chang, C.-C. Ou, and J. Y. H. Chan Up-Regulation of Glutamate Receptors in Nucleus Tractus Solitarii Underlies Potentiation of Baroreceptor Reflex by Heat Shock Protein 70 Mol. Pharmacol., May 1, 2002; 61(5): 1097 - 1104. [Abstract] [Full Text] [PDF]

				S. H.F. Luoh and S. H.H. Chan Inhibition of Baroreflex by Angiotensin II via Fos Expression in Nucleus Tractus Solitarii of the Rat Hypertension, July 1, 2001; 38(1): 130 - 135. [Abstract] [Full Text] [PDF]

				P.-L. Li, Y.-M. Chao, S. H. H. Chan, and J. Y. H. Chan Potentiation of Baroreceptor Reflex Response by Heat Shock Protein 70 in Nucleus Tractus Solitarii Confers Cardiovascular Protection During Heatstroke Circulation, April 24, 2001; 103(16): 2114 - 2119. [Abstract] [Full Text] [PDF]

				T. B. J. Kuo and C. C. H. Yang Altered frequency characteristic of central vasomotor control in SHR Am J Physiol Heart Circ Physiol, January 1, 2000; 278(1): H201 - H207. [Abstract] [Full Text] [PDF]

				J. C. Yen, J. Y. H. Chan, and S. H. H. Chan Differential Roles of NMDA and Non-NMDA Receptors in Synaptic Responses of Neurons in Nucleus Tractus Solitarii of the Rat J Neurophysiol, June 1, 1999; 81(6): 3034 - 3043. [Abstract] [Full Text] [PDF]

				W.-B. Len and J. Y. H. Chan Glutamatergic projection to RVLM mediates suppression of reflex bradycardia by parabrachial nucleus Am J Physiol Heart Circ Physiol, May 1, 1999; 276(5): H1482 - H1492. [Abstract] [Full Text] [PDF]

				J. Y. H. Chan, W.-C. Chen, H.-Y. Lee, and S. H. H. Chan Elevated Fos Expression in the Nucleus Tractus Solitarii Is Associated With Reduced Baroreflex Response in Spontaneously Hypertensive Rats Hypertension, November 1, 1998; 32(5): 939 - 944. [Abstract] [Full Text] [PDF]

				K.-R. Hwang, S. H. H. Chan, and J. Y. H. Chan Noradrenergic neurotransmission at PVN in locus ceruleus-induced baroreflex suppression in rats Am J Physiol Heart Circ Physiol, April 1, 1998; 274(4): H1284 - H1292. [Abstract] [Full Text] [PDF]

				J. Y. H. Chan, C.-D. Shih, and S. H. H. Chan Enhancement of spontaneous baroreflex by antisense c-fos oligonucleotide treatment in the NTS of the rat Am J Physiol Heart Circ Physiol, November 1, 1997; 273(5): H2200 - H2208. [Abstract] [Full Text] [PDF]