Abstract: The invention is directed to nitric oxide (NO) donor compounds and to pharmaceutical compositions containing such nitric oxide (NO) donor compounds, for delivering NO to the apical surface of a mucosa, where the nitric oxide is released for passage across the epithelial monolayer of the mucous membrane. The NO donor compounds include polyalkyleneamine NO donors as well as tertiary and quaternary amino aliphatic NO donor compounds. The compounds and compositions of the invention are useful in any situation in which it is desirable to deliver NO across a mucosal surface. For example, the compounds and compositions of the invention are particularly useful in treating pulmonary hypertension, male impotence, and several other specific conditions.