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 (CaV3.1) and normo- and hypertensive rats was examined.
Changes in afferent arteriolar diameter in the kidneys
from wild-type and CaV3.1 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 CaV3.1 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
CaV3.1 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.
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 (CaV3.1) and normo- and hypertensive rats was examined.
Changes in afferent arteriolar diameter in the kidneys
from wild-type and CaV3.1 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 CaV3.1 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
CaV3.1 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.
| Original language | English |
|---|---|
| Journal | Pflügers Archiv - European Journal of Physiology |
| Volume | 468 |
| Issue number | 4 |
| Pages (from-to) | 541-550 |
| Number of pages | 10 |
| ISSN | 0031-6768 |
| DOIs | |
| Publication status | Published - 1 Apr 2016 |
Keywords
- Faculty of Health and Medical Sciences
- renal blood flow
- Autoregulation
- Calcium channel
- Renal vascular resistance