Linoleic acid-rich (LAR), linolenic acid-rich (LNAR) and linoleic acid-deficient (LAD) diets in spontaneously hypertensive rats (SHR) and normotensive rats (NR) resulted in various changes in n-6 and n-3 fatty acids of lipids in renal medulla. After LAR diets the percentage of linoleic (LA) and arachidonic acids (AA) was high only in triglycerides (TG) and free fatty acids (FFA). In phosphatidylethanolamine (PE) LA was increased after LAR diet, whereas AA remained unchanged. In phosphatidylcholine (PC) LA was higher, but AA appeared lower as compared to LAD fed SHR. After LNAR diet linolenic (LNA) and eicosapentaenoic acids (EPA) were increased, but AA appeared significantly lower. Consequently, the lowest percentage of AA was found after LNAR diet. Blood pressure could not be influenced by the diets.