P10.04 INFLUENCE OF 1,25(OH)2D3 (VITAMIN D) ON RESISTANCE ARTERY CONTRACTILITY

DOI

10.1016/j.artres.2009.10.135How to use a DOI?

Abstract

Low serum vitamin D is linked with higher vascular risk. It is unclear how.

Objective: to test whether 1,25(OH)₂D₃ (active vitamin D) modifies contractility of proximal resistance vessels, dose-dependently.

Methods: Male Wistar rat mesenteric arteries were investigated by wire myography. 60mM High Potassium Physiological Salt Solution (KPSS) was the reference for contraction and relaxation measurements. Noradrenaline (NA) responses were measured after 10min, 30min and 3hours incubation with 1,25(OH)₂D₃, as was endothelial function by Acetylcholine (Ach) response.

Results: KPSS-induced contraction was unaffected by 1,25(OH)₂D₃, but slightly decreased after 3h incubation in control and 1,25(OH)₂D₃ groups (generally n=5 arteries each). After 10min NA-induced contraction at 10⁻⁵M, a small dose response occurred (controls 192±22%; vitD 10nM 183%, 100nM 169%), but after 3h incubation with 100nM 1,25(OH)₂D₃, contraction decreased at 3x10⁻⁶, and at 10⁻⁵M NA to 118.6±10.3%, compared with controls (mean± SE: 145.4 ±13.9%). While differences were individually ‘significant’ (p=0.04, Wilcoxon test), 2-way ANOVA demonstrated clear vitD (F_3,80 6.3,p=0.001) and NA effects (F_4,80 p<0.000), without interaction. Ach-induced relaxation (at 10⁻⁹ to 10⁻⁵M) after 30min incubation was not enhanced by any 1,25(OH)2D3 dose. After 3h, higher concentration Ach (10⁻⁶, 10⁻⁵M) induced constriction. Paradoxically, 100nM 1,25(OH)₂D₃ marginally increased contractions (105.2±4.8%; control 91.7±4.7%), not individually ‘significant’ but by 2-way Anova, both vitD & Ach dose effects were (F_3,78=6.6, p<0.001).

Conclusion: To our knowledge, these are the first vitD experiments on proximal resistance vessels. 100nM vitamin D may decrease NA-induced contraction but paradoxical endothelial effects may underlie its variable in-vivo actions.

Open Access

This is an open access article distributed under the CC BY-NC license.

TY  - JOUR
AU  - G. Goudot
AU  - M. Rezai
AU  - J.K. Cruickshank
PY  - 2009
DA  - 2009/12/03
TI  - P10.04 INFLUENCE OF 1,25(OH)2D3 (VITAMIN D) ON RESISTANCE ARTERY CONTRACTILITY
JO  - Artery Research
SP  - 191
EP  - 192
VL  - 3
IS  - 4
SN  - 1876-4401
UR  - https://doi.org/10.1016/j.artres.2009.10.135
DO  - 10.1016/j.artres.2009.10.135
ID  - Goudot2009
ER  -