On the basis of our observations and those of others, 3 important mechanisms may be involved in the protective effects of maternal citrulline on the developmental programming of kidney disease and hypertension in the STZ offspring: upregulation of DDAH-2 and DDAH activity, reduction of renal ADMA, and restoration of NO bioavailability in the kidney (Fig. 8). The gene discussed is DDAH1; the disease is hypertensive disorder.