We found a match
Your institution may have access to this item. Find your institution then sign in to continue.
- Title
No apparent role for T-type Ca channels in renal autoregulation.
- Authors
Frandsen, Rasmus; Salomonsson, Max; Hansen, Pernille; Jensen, Lars; Braunstein, Thomas; Holstein-Rathlou, Niels-Henrik; Sorensen, Charlotte
- Abstract
Renal autoregulation protects glomerular capillaries against increases in renal perfusion pressure (RPP). In the mesentery, both L- and T-type calcium channels are involved in autoregulation. L-type calcium channels participate in renal autoregulation, but the role of T-type channels is not fully elucidated due to lack of selective pharmacological inhibitors. The role of T- and L-type calcium channels in the response to acute increases in RPP in T-type channel knockout mice (Ca3.1) and normo- and hypertensive rats was examined. Changes in afferent arteriolar diameter in the kidneys from wild-type and Ca3.1 knockout mice were assessed. Autoregulation of renal blood flow was examined during acute increases in RPP in normo- and hypertensive rats under pharmacological blockade of T- and L-type calcium channels using mibefradil (0.1 μM) and nifedipine (1 μM). In contrast to the results from previous pharmacological studies, genetic deletion of T-type channels Ca3.1 did not affect renal autoregulation. Pharmacological blockade of T-type channels using concentrations of mibefradil which specifically blocks T-type channels also had no effect in wild-type or knockout mice. Blockade of L-type channels significantly attenuated renal autoregulation in both strains. These findings are supported by in vivo studies where blockade of T-type channels had no effect on changes in the renal vascular resistance after acute increases in RPP in normo- and hypertensive rats. These findings show that genetic deletion of T-type channels Ca3.1 or treatment with low concentrations of mibefradil does not affect renal autoregulation. Thus, T-type calcium channels are not involved in renal autoregulation in response to acute increases in RPP.
- Subjects
CALCIUM channels; BLOOD flow; KNOCKOUT mice; KIDNEY blood-vessels; MIBEFRADIL (Drug); PERFUSION; LABORATORY mice
- Publication
Pflügers Archiv: European Journal of Physiology, 2016, Vol 468, Issue 4, p541
- ISSN
0031-6768
- Publication type
Article
- DOI
10.1007/s00424-015-1770-9