MLR stimulation and exercise pressor reflex activate different renal sympathetic fibers in decerebrate cats

Shawn G. Hayes, Marc Kaufman

Research output: Contribution to journalArticle

26 Citations (Scopus)

Abstract

Although mesencephalic locomotor region (MLR) stimulation and the exercise pressor reflex have been shown to increase whole nerve renal sympathetic activity, it is not known whether these mechanisms converge onto the same population of renal sympathetic postganglionic efferents. In decerebrate cats, we examined the responses of single renal sympathetic postganglionic efferents to stimulation of the MLR and the exercise pressor reflex (i.e., static contraction of the triceps surae muscles). We found that, in most instances (24 of 28 fibers), either MLR stimulation or the muscle reflex, but not both, increased the discharge of renal postganglionic sympathetic efferents. In addition, we found that renal sympathetic efferents that responded to static contraction while the muscles were freely perfused responded more vigorously to static contraction during circulatory arrest. Moreover, stretch of the calcaneal (Achilles) tendon stimulated the same renal sympathetic efferents as did static contraction. These findings suggest that MLR stimulation and the exercise pressor reflex do not converge onto the same renal sympathetic postganglionic efferents.

Original languageEnglish (US)
Pages (from-to)1628-1634
Number of pages7
JournalJournal of Applied Physiology
Volume92
Issue number4
DOIs
StatePublished - Jan 1 2002

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Adrenergic Fibers
Reflex
Cats
Kidney
Achilles Tendon
Muscles
Muscle Contraction

All Science Journal Classification (ASJC) codes

  • Physiology
  • Physiology (medical)

Cite this

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MLR stimulation and exercise pressor reflex activate different renal sympathetic fibers in decerebrate cats. / Hayes, Shawn G.; Kaufman, Marc.

In: Journal of Applied Physiology, Vol. 92, No. 4, 01.01.2002, p. 1628-1634.

Research output: Contribution to journalArticle

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