Abstract: Use of proanthocyanidins as an active ingredient of a stimulator as a source of arginine and a source of nitric oxide in the treatment of erectile dysfunction. The active ingredient stimulates the endothelial NO-synthase enzyme, which acts as a catalyst for the synthesis of nitric oxide from its substrate L-arginine or its salts. The nitric oxide in turn activates theguanylyl cyclase, which leads to an increased development of cyclic guanosine monophosphate, which causes relaxation of smooth muscles. Blood vessel diameter may increase. The stimulator may also have Sildenafil or enzymes that inhibit an enzyme phosphodiesterase type5 from reducing an amount of the cyclic guanosine monophosphate. The substrate may be amino acid L-arginine, arginine salts or a dipeptide of arginine and aspartic acid.

Abstract: A medicinal composition for treating dysmenorrhea and endometriosis comprising a plant extract and containing proanthocyanidins as an effective component thereof. The composition is provided and administered in the form of soft capsules, tablets, or a powdery or liquid preparation to be used for treating dysmenorrhea and endometriosis.