Journal
AMERICAN JOURNAL OF PHYSIOLOGY-RENAL PHYSIOLOGY
Volume 297, Issue 2, Pages F510-F516Publisher
AMER PHYSIOLOGICAL SOC
DOI: 10.1152/ajprenal.00116.2009
Keywords
adenosine 5 '-diphosphate-ribosyl cyclase; calcium mobilization; vascular smooth muscle cells; renal circulation
Categories
Funding
- National Heart, Lung, and Blood Institute [HL-02334]
- Biological Sciences Research Council [BB/D012694/1]
- Biotechnology and Biological Sciences Research Council [BB/D012694/1, BB/G008523/1] Funding Source: researchfish
- BBSRC [BB/G008523/1, BB/D012694/1] Funding Source: UKRI
Ask authors/readers for more resources
Thai TL, Churchill GC, Arendshorst WJ. NAADP receptors mediate calcium signaling stimulated by endothelin-1 and norepinephrine in renal afferent arterioles. Am J Physiol Renal Physiol 297: F510-F516, 2009. First published May 13, 2009; doi:10.1152/ajprenal.00116.2009.-The enzyme ADP-ribosyl (ADPR) cyclase plays a significant role in mediating increases in renal afferent arteriolar cytosolic calcium concentration ([Ca2+](i)) in vitro and renal vasoconstriction in vivo. ADPR cyclase produces cyclic ADP ribose, a second messenger that contributes importantly to ryanodine receptor-mediated Ca2+ mobilization in renal vascular responses to several vasoconstrictors. Recent studies in nonrenal vascular smooth muscle cells (VSMC) have shown that nicotinic acid adenine dinucleotide phosphate (NAADP), another second messenger generated by ADPR cyclase, may contribute to Ca2+ signaling. We tested the hypothesis that a Ca2+ signaling pathway involving NAADP receptors participates in afferent arteriolar [Ca2+](i) responses to the G protein-coupled receptor agonists endothelin-1 (ET-1) and norepinephrine (NE). To test this, we isolated rat renal afferent arterioles and measured ([Ca2+](i))using fura-2 fluorescence. We compared peak ([Ca2+](i)) increases stimulated by ET-1 and NE in the presence and absence of inhibitors of acidic organelle-dependent Ca2+ signaling and NAADP receptors. Vacuolar H+-ATPase inhibitors bafilomycin A1 and concanamycin A, disruptors of pH and Ca2+ stores of lysosomes and other acidic organelles, individually antagonized ([Ca2+](i)) responses to ET-1 and NE by 40-50% (P < 0.05). The recently discovered NAADP receptor inhibitor Ned-19 attenuated ([Ca2+](i)) responses to ET-1 or NE by 60-70% (P < 0.05). We conclude that NAADP receptors contribute to both ET-1 and NE-induced ([Ca2+](i)) responses in afferent arterioles, an effect likely dependent on acidic vesicle, possibly involving lysosome, signaling in VSMC in the renal microcirculation.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available