Source:http://linkedlifedata.com/resource/umls/id/C0030350
MSH: An alkaloid found in opium but not closely related to the other opium alkaloids in its structure or pharmacological actions. It is a direct-acting smooth muscle relaxant used in the treatment of impotence and as a vasodilator, especially for cerebral vasodilation. The mechanism of its pharmacological actions is not clear, but it apparently can inhibit phosphodiesterases and it may have direct actions on calcium channels.,CSP: opium alkaloid used as a smooth muscle relaxant and weak analgesic.,PDQ: An opiate alkaloid isolated from the plant Papaver somniferum and produced synthetically. As a direct-acting smooth muscle relaxant, papaverine is not closely related to the other opium alkaloids in structure or pharmacological actions; its mechanism of action may involve the non-selective inhibition of phosphodiesterases and direct inhibition of calcium channels. This agent also exhibits antiviral activity against respiratory syncytial virus, cytomegalovirus, and HIV. Check for "http://www.cancer.gov/Search/Cl