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NASA NTRS · 20040141480

Vestibular stimulation leads to distinct hemodynamic patterning

Kerman, I. A.·Emanuel, B. A.·Yates, B. J.
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Abstract

Previous studies demonstrated that responses of a particular sympathetic nerve to vestibular stimulation depend on the type of tissue the nerve innervates as well as its anatomic location. In the present study, we sought to determine whether such precise patterning of vestibulosympathetic reflexes could lead to specific hemodynamic alterations in response to vestibular afferent activation. We simultaneously measured changes in systemic blood pressure and blood flow (with the use of Doppler flowmetry) to the hindlimb (femoral artery), forelimb (brachial artery), and kidney (renal artery) in chloralose-urethane-anesthetized, baroreceptor-denervated cats. Electrical vestibular stimulation led to depressor responses, 8 +/- 2 mmHg (mean +/- SE) in magnitude, that were accompanied by decreases in femoral vasoconstriction (23 +/- 4% decrease in vascular resistance or 36 +/- 7% increase in vascular conductance) and increases in brachial vascular tone (resistance increase of 10 +/- 6% and conductance decrease of 11 +/- 4%). Relatively small changes (<5%) in renal vascular tone were observed. In contrast, electrical stimulation of muscle and cutaneous afferents produced pressor responses (20 +/- 6 mmHg) that were accompanied by vasoconstriction in all three beds. These data suggest that vestibular inputs lead to a complex pattern of cardiovascular changes that is distinct from that which occurs in response to activation of other types of somatic afferents.

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NASA Discipline NeuroscienceNon-NASA CenterVestibular Nerve/physiologyVestibule/innervation/physiologyHemodynamic Processes/physiologyCatsSympathectomySupport, Non-U.S. Gov'tAnimalsHeart Rate/physiologyHindlimb/blood supply/physiologyForelimb/blood supply/physiologyPressoreceptors/physiology/surgeryBrachial Artery/physiologyElectric StimulationKidney/blood supply/physiologyRegional Blood Flow/physiologySupport, U.S. Gov't, P.H.SVascular Resistance/physiologyLaser-Doppler FlowmetrySupport, U.S. Gov't, Non-P.H.SBlood Pressure/physiologyAnalysis of VarianceReaction Time/physiology

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BibTeXRIS

Kerman, I. A., Emanuel, B. A., Yates, B. J.. 2000-07-01. Vestibular stimulation leads to distinct hemodynamic patterning. https://ntrs.nasa.gov/citations/20040141480

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