COL4A1 and COL4A1/A2-related disorder: We set out to investigate CSVD mechanisms by assessing vascular function in small mesenteric arteries of a mouse model of Gould syndrome, Col4a1+/SVC that carries a heterozygous missense mutation in Col4a1 (G1064D)11,20 which substitutes a glycine residue for aspartic acid in the collagen domain of α1α1α2(IV).