Impaired excitability of renal afferent innervation after exposure to the inflammatory chemokine cxcl1.

IMPAIRED EXCITABILITY OF RENAL AFFERENT INNERVATION AFTER EXPOSURE TO THE INFLAMMATORY CHEMOKINE CXCL1. Am J Physiol Renal Physiol. 2015 Dec 23;:ajprenal.00189.2015 Authors: Ditting T, Freisinger W, Rodionova K, Schatz J, Lale N, Heinlein S, Linz P, Ott C, Schmieder RE, Scrogin KE, Veelken R 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 (DRG) neurons (Th11-L2), retrogradely labelled with of DiI, were incubated with CXCL1 (20 hours) or vehicle prior to 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 labelled renal afferents treated with vehicle, 58.9% exhibited a tonic firing pattern vs. 7.8%, in unlabelled, non-renal neurons (P<0.05). However, after exposure to CXCL1 significantly more "phasic neurons" were found among labelled 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 contro...
Source: Am J Physiol Renal P... - Category: Urology & Nephrology Authors: Tags: Am J Physiol Renal Physiol Source Type: research