The aim of our study was to identify whether vitamin-D deficiency (VDD) can alter the geometry of the coronary-resistance-artery system. Male Wistar rats were divided into vitamin-D-deficient (VD-, n = 10) and vitamin-D-supplemented (VD+, n = 8) groups. After eight weeks, branches and segments of the left-anterior-descending-coronary-artery (LAD) network were analyzed by a video-microscopy technique. Segments were divided into 50 μm-long cylindrical ring units. VDD did not increase the number of morphological abnormalities. The number of segments did not differ between the groups (VD-: 210 and VD+: 224; pooled data of 8 networks). A larger lumen area of branches was found in VD+ group, while 1-4-order branches were lengthier in the VD- group. VD- rats had less rich coronary-resistance-artery networks in terms of 50 µm-long units. (VD-: 6365 vs. VD+: 6602; pooled data of 8 networks). VD+ animals were richer in the 100-350 µm outer diameter range, and VD- animals were richer in the 400-550 µm-diameter units. In VD- rats, 150-200 and 300 µm units were almost missing at higher flow distances from the orifice. Serum vitamin-D alterations caused by dietary changes can affect the geometry of the coronary-artery network, which may contribute to vitamin-D-dependent changes in cardiovascular mortality.
Keywords: LAD; cardiovascular disease; left-anterior-descending coronary arteries; network; video-microscopic technique; vitamin-D deficiency.