Olfactory bulbectomy attenuates cardiovascular sympathoexcitatory reflexes in rats

Am J Physiol Heart Circ Physiol. 2002 Dec;283(6):H2575-83. doi: 10.1152/ajpheart.00164.2002. Epub 2002 Aug 22.

Abstract

Bilateral removal of the olfactory lobes in rats produces a number of behavioral, endocrine, and neurochemical alterations in the brain. Little is known, however, regarding the effects of this treatment on cardiovascular function and autonomic reflexes. Male Sprague-Dawley rats underwent bilateral surgical ablation of the olfactory bulbs (n = 10) or were sham operated (n = 8). After 3 wk of recovery, animals were instrumented with femoral catheters and a lumbar sympathetic nerve recording electrode. After 24 h of recovery, cardiovascular responses to arterial baroreflex manipulation, air jet stress, and smoke exposure were recorded. Olfactory bulbectomized rats demonstrated attenuated sympathoexcitatory responses to hypotension, air jet stress, and smoke exposure, as well as elevated basal blood pressure, compared with sham-operated rats. These data indicate that the integrity of the olfactory bulbs in rats is important for the elicitation of normal cardiovascular and autonomic responses to a number of evocative stimuli.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Baroreflex / physiology
  • Blood Pressure / drug effects
  • Blood Pressure / physiology
  • Cardiovascular System / innervation*
  • Catheterization
  • Electrodes, Implanted
  • Ganglionic Blockers / pharmacology
  • Heart Rate / physiology
  • Lumbosacral Region
  • Male
  • Neurosurgical Procedures
  • Olfactory Bulb / physiology*
  • Olfactory Bulb / surgery
  • Rats
  • Rats, Sprague-Dawley
  • Reflex, Abnormal / physiology*
  • Smoke / adverse effects
  • Stress, Physiological
  • Sympathetic Nervous System / physiology*
  • Synaptic Transmission / physiology

Substances

  • Ganglionic Blockers
  • Smoke