SulfonesPurinesPiperazinesPhosphodiesterase InhibitorsPhosphodiesterase 5 Inhibitors3',5'-Cyclic-GMP PhosphodiesterasesErectile DysfunctionCyclic Nucleotide Phosphodiesterases, Type 5Alternative SplicingPenile ErectionHomosexuality, MaleMethamphetamineVasodilator AgentsCyclic GMPGeorgiaUnsafe SexRisk-TakingSexual BehaviorComplement Pathway, AlternativeAnimal Testing AlternativesExonsMolecular Sequence DataComplementary TherapiesBase SequenceProtein IsoformsAmino Acid SequenceRNA, MessengerRNA Splice SitesRNA SplicingIntronsRNA PrecursorsComplement Factor BTreatment Outcome