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Adrenomedullin, which is produced by the vascular endothelial and smooth muscle cells and cardiomyocytes, is considered to be a local factor controlling vascular tone, cardiac contractility, and renal sodium excretion. Hypertension is the most common cause of cardiovascular disorders and diseases. Exercise has beneficial effects on hypertension, but pathophysiological factors involved in exercise‐mediated amelioration of hypertension are yet to be elucidated. We hypothesized that adrenomedullin produced through exercise could play an essential role in the protection from hypertension. For this study rats were subjected to swimming training for six weeks (1‐h per day and five times each week). Meanwhile, hypertension was induced by the oral administration of L‐NAME (60 mg/kg). Here, we show that L‐NAME administration per se leads to a significant increase in mean arterial blood pressure. Notably, the 6‐week swimming exercise causes a protective effect from the development of hypertension. In addition, the rats rescued from hypertension have high mRNA levels of renal adrenomedullin while they have low levels of adrenomedullin mRNA in the aorta. The obtained data indicate that a 6‐week exercise intervention rescues rats from high blood pressure by leading to changes in adrenomedullin levels in the aorta and kidney. The increased expression of adrenomedullin in the aorta might have been a result that compensates for the hypertensive effect of L‐NAME. On the other hand, exercise probably exerts its protective effects on hypertension by increasing adrenomedullin in the kidney. A more extended exercise period may give more apparent results regarding the level of adrenomedullin in different organs.