Hypertensive kidney disease this situation, the kidney supplied blood by the narrowed renal artery suffers from inadequate blood flow, which in turn causes the size of the kidneys to decrease. Other consequences include arterial stiffening, which involves a gradual breakdown of elastic fibers and intima (the innermost layer of a blood vessel) thickening. An alternative mechanism of hypertensive nephropathy is prolonged glomerular hypertension and hence glomerular hyperfiltration. These can occur simultaneously but not necessarily. The idea is that hypertension results in sclerosis of the glomeruli which ultimately means reduced kidney function. As a compensatory mechanism, the unaffected nephrons (specifically, the preglomerular arterioles) vasodilate
Anterior cerebral artery the embryo. The anterior cerebral artery shows considerable variation. In a study made using MRA, the most common variation was an underdeveloped A1 segment (5.6%), followed by the presence of an extra A2 segment (3%). In 2% of cases there was only one A2 segment. The anterior cerebral artery supplies a part of the frontal lobe, specifically its medial surface and the upper border. It also supplies the front four–fifths of the corpus callosum, and provides blood to deep structures such as the anterior limb of the internal capsule, part of the caudate nucleus, and the anterior part of the