Analysis of the gene networks in 20-day-old and 5- and 18-month-old animals revealed that the common genes probably play a significant role in the regulation of blood vessel processes in the hippocampus of OXYS rats during development of AD-like pathology: Nos1, P2rx4, Pla2g6, and Bdkrb2. Taken together, these results indicate that in OXYS rats, the development of AD signs is preceded by changes in the expression of hippocampal genes involved in cerebrovascular processes; these changes increased with the progression of disease pathology. This evidence concerns the gene NOS1 and Alzheimer disease.