This Article Full Text Full Text (PDF) All Versions of this Article: 47/3/527    most recent 01.HYP.0000199984.78039.36v1 Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Linz, P. Articles by Veelken, R. Search for Related Content PubMed PubMed Citation Articles by Linz, P. Articles by Veelken, R. Related Collections Animal models of human disease Hypertension - basic studies Autonomic, reflex, and neurohumoral control of circulation Other Vascular biology

(Hypertension. 2006;47:527.)
© 2006 American Heart Association, Inc.

Part 2 Original Articles

Sensory Neurons With Afferents From Hind Limbs

Enhanced Sensitivity in Secondary Hypertension

Peter Linz; Kerstin Amann; Wolfgang Freisinger; Till Ditting; Karl F. Hilgers; Roland Veelken

From the Department of Internal Medicine 4/Nephrology and Hypertension (P.L., W.F., T.D., K.F.H., R.V.), Department of Pathology (K.A.), University of Erlangen-Nürnberg, Erlangen, Germany.

Correspondence to Roland Veelken, Department of Medicine 4, University of Erlangen-Nürnberg, Loschgestraße 8, 91054 Erlangen, Germany. E-mail mfm431{at}rzmail.uni-erlangen.de

Sensory nerve fibers from the dorsal root ganglia (DRG) may contribute to the regulation of peripheral vascular resistance. Axons of DRG neurons of the lower thoracic cord project mainly to resistance vessels in the lower limbs, likely opposing the vasoconstrictor effects of the sympathetic activity. This mechanism might be of importance in hypertension with increased sympathetic activity. We tested the hypothesis that sensory neurons of the DRG in the lower thoracic cord show an altered sensitivity to mechanical stimuli in hypertension. Neurons from DRG (T11 to L1) of rats with hypertension (2 kidney-1 clip hypertensive rats and 5 of 6 nephrectomized rats) were cultured on coverslips. Current time relationships were established with whole-cell patch recordings. Cells were characterized under control conditions and after exposure to hypoosmotic solutions to induce mechanical stress. Neurons with projections to the kidney were studied for comparison. The hypoosmotic extracellular medium induced a significant change in conductance of the cells in all of the groups of rats. In hypertensive rats, responses of cells with hindlimb axons were significantly different from controls: (2 kidney-1 clip hypertensives: –351±52 pA and 5 of 6 nephrectomized rats: –372±43 pA versus controls: –190±25 pA; P<0.05). Responses of DRG cells with renal afferents to mechanical stress were unaffected. Neurons from DRG in the lower thoracic cord with projections to the lower limbs exhibited an increased sensitivity to mechanical stress. We speculate that this observation may indicate an increased activity of these neurons, their axons, and neurotransmitters in the control of resistance vessels in hypertension.

Key Words: hindlimb • hypertension, renal • mechanosensitivity • hypertension, secondary • kidney • nephrectomy • rats

This article has been cited by other articles:

				T. Ditting, G. Tiegs, K. Rodionova, P. W. Reeh, W. Neuhuber, W. Freisinger, and R. Veelken Do distinct populations of dorsal root ganglion neurons account for the sensory peptidergic innervation of the kidney? Am J Physiol Renal Physiol, November 1, 2009; 297(5): F1427 - F1434. [Abstract] [Full Text] [PDF]