Autonomic DysreflexiaSpinal Cord InjuriesQuadriplegiaAutonomic Nervous System DiseasesBlood PressureReflex, AbnormalIntracranial Hemorrhage, HypertensiveParaplegiaReflexAutonomic Fibers, PreganglionicHypertensionGalvanic Skin ResponsePressureDoxazosinUrodynamicsRectumHeart RateBlood Pressure DeterminationBlood Pressure Monitoring, AmbulatoryThoracic VertebraeAfferent PathwaysAdrenergic alpha-AntagonistsReceptors, Adrenergic, alphaCervical VertebraeRats, WistarColon