Impaired excitability of renal afferent innervation after exposure to the inflammatory chemokine CXCL1 Journal Article


Authors: Ditting, T.; Freisinger, W.; Rodionova, K.; Schatz, J.; Lale, N.; Heinlein, S.; Linz, P.; Ott, C.; Schmieder, R. E.; Scrogin, K. E.; Veelken, R.
Article Title: Impaired excitability of renal afferent innervation after exposure to the inflammatory chemokine CXCL1
Abstract: Recently, we showed that renal afferent neurons exhibit a unique firing pattern, i.e., predominantly sustained firing, upon stimulation. Pathological conditions such as renal inflammation likely alter excitability of renal afferent neurons. Here, we tested whether the proinflammatory chemokine CXCL1 alters the firing pattern of renal afferent neurons. Rat dorsal root ganglion neurons (Th11-L2), retrogradely labeled with dicarbocyanine dye, were incubated with CXCL1 (20 h) or vehicle before patch-clamp recording. The firing pattern of neurons was characterized as tonic, i.e., sustained action potential (AP) firing, or phasic, i.e., 5 APs following current injection. Of the labeled renal afferents treated with vehicle, 58.9% exhibited a tonic firing pattern vs. 7.8%, in unlabeled, nonrenal neurons (P 0.05). However, after exposure to CXCL1, significantly more phasic neurons were found among labeled renal neurons; hence the occurrence of tonic neurons with sustained firing upon electrical stimulation decreased (35.6 vs. 58.9%, P 0.05). The firing frequency among tonic neurons was not statistically different between control and CXCL1-treated neurons. However, the lower firing frequency of phasic neurons was even further decreased with CXCL1 exposure [control: 1 AP/600 ms (1-2) vs. CXCL1: 1 AP/600 ms (1-1); P 0.05; median (25th-75th percentile)]. Hence, CXCL1 shifted the firing pattern of renal afferents from a predominantly tonic to a more phasic firing pattern, suggesting that CXCL1 reduced the sensitivity of renal afferent units upon stimulation.
Journal Title: American journal of physiology.Renal physiology
Volume: 310
Issue: 5
ISSN: 1522-1466; 1522-1466
Publisher: the American Physiological Society  
Journal Place: United States
Date Published: 2016
Start Page: F364
End Page: 71
Language: eng
DOI/URL:
Notes: CI: Copyright (c) 2016; JID: 100901990; OTO: NOTNLM; 2015/05/04 [received]; 2015/12/15 [accepted]; 2015/12/23 [aheadofprint]; ppublish