Common pathological changes seen in the kidney in benign hypeension are-

Microscopically there is a narrowing of the lumens of the aerioles and small aeries, caused by thickening and hyalinization of the walls (hyaline aeriolosclerosis). In addition, interlobular and arcuate aeries show medial hyperophy, replication of internal elastic lamina, all of which narrow the lumen. Parenchymal changes: As a consequence of ischemia, there is a variable degree of atrophy of parenchyma. This includes glomerular shrinkage, eposition of collagen in Bowman's space, periglomerular fibrosis, tubular atrophy, and fine interstitial fibrosis. From Textbook of pathology Harsh Mohan 7th edition, pg no:678, Pathologic basis of disease Robbins South Asian edition(9), pg no:938,939