Vitamin D Deficiency and Gender Alter Vasoconstrictor and Vasodilator Reactivity in Rat Carotid Artery

Figures

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  Figure 1. Contraction ability of isolated carotid artery segments: (A) phenylephrine (Phe)-induced contraction in the four experimental groups at 10−6 mol/L Phe concentration. Male gender and vitamin D deficiency were associated with more pronounced relative contraction. Data are shown as individual data points; horizontal lines represent mean ± SD. Two-way ANOVA; factors: gender, vitamin D status. **: p < 0.01, ***: p < 0.001. (B) Phe-induced contraction. Male rats showed significantly increased contraction compared to females at Phe concentration of 10−7 mol/L independently from vitamin D status. Vitamin D deficient female vessels had stronger contraction compared to their vitamin D supplemented counterparts. At Phe concentration of 10−6 mol/L, MD− arteries contracted more than FD− ones. Vitamin D deficient male rats showed increased contraction compared to their vitamin D supplemented counterparts. Data are shown as mean ± SEM; n = 9–11 in each group; repeated measures ANOVA, Bonferroni’s post hoc test; aa: p < 0.01 FD+ vs. FD−, bb: p < 0.01 FD+ vs. MD+, ccc: p < 0.001 FD+ vs. MD−, e: p < 0.05 FD− vs. MD−, eee: p < 0.001 FD− vs. MD−, f: p < 0.05 MD+ vs. MD−. Phe-induced contractions in…

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  Figure 2. Relaxation ability of isolated carotid artery segments: (A) acetylcholine (Ach)-induced relaxation in the four experimental groups at 10−6 mol/L Ach concentration. Male gender was associated with less pronounced relative relaxation. Data are shown as individual data points; horizontal lines represent mean ± SD. Two-way ANOVA; factors: gender, vitamin D status. ***: p < 0.001. (B) Ach-induced relaxation. Male rats showed significantly reduced relaxation compared to females at Ach concentration of 10−6 mol/L independently from vitamin D status. Data are shown as mean ± SEM; n = 9–11 in each group; repeated measures ANOVA, Bonferroni’s post hoc test; bb: p < 0.01 FD+ vs. MD+, ccc: p < 0.001 FD+ vs. MD−, eee: p < 0.001 FD− vs. MD−. Ach-induced relaxation in the presence of L-NAME and/or indomethacin (INDO) or their vehicle DMSO (C) in female vitamin D supplemented rats (FD+), (D) in female vitamin D deficient rats (FD−), (E) in male vitamin D supplemented rats (MD+) and (F) in male vitamin D deficient rats (MD−). L-NAME blocked the vasodilation in all experimental groups, co-incubation with INDO had no additional effect. INDO itself increased the degree of relaxation only in both…

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  Figure 3. Histological changes of the carotid arteries: (A) elastic fiber density of carotid artery segments. Tissue sections were stained by the purple-colored resorcin-fuchsin stain. Vitamin D deficient female and male arteries showed significantly lower optical density than vitamin D supplemented female vessels. (B) Representative images of resorcin-fuchsin-stained carotid artery sections. (C) Alpha smooth muscle actin (SMA) immunohistochemical labeling intensity in the media layer of carotid arteries. In vitamin D deficient male rats, the measured optical density was significantly lower compared to vitamin D supplemented male animals. (D) Representative images of carotid arteries stained against SMA. (E) Thromboxane A2 receptor (TP) density of carotid arteries. Vitamin D deficient male rats showed higher receptor density compared to vitamin-supplemented male and female animals. (F) Representative images of TP-stained vessels. (G) Optical density of eNOS labeling in the intimal layer of carotid arteries. Vitamin D deficiency induced a significant decrease in eNOS staining intensity in males. (H) Representative images of vessels labeled with anti-eNOS antibody. (I) 3-Nitrotyrosine (NT)…