Considering aorta angiotensin II response has been used as a surrogate measure of large artery disease [9], in this work, we, therefore, intend to study the effect of GDM on vascular function, considering (1) if GDM increases Ang II induced vasoconstriction (2) if GDM changes the interaction between adrenergic alpha-1 and Ang II AT1 receptors in this vessel and (3) The participation of NOS and COX in such changes in the rat aorta. The gene discussed is NOS2; the disease is gestational diabetes.