Nitric oxide is used for treatment of pulmonary hypertension via which route -

Ans. is 'a' i.e., Inhalational Inhaled Nitric oxide* Inhaled nitric oxide gas is an important development in the management of pulmonary hypertension.* It is delivered directly to the pulmonary circulation.* Nitric oxide acts on the vascular smooth muscle. It produces relaxation by acting on smooth muscle guanylate cyclase to produce cGMP which acts on series of protein kinases and resuces intracellular calcium levels to produce muscle relaxation.* Nitric oxide in blood is rapidly bound and inactivated, thus inhaled nitric oxide has minimal effect on systemic circulation and functions as specific pulmonary vasodilator.