Abstract: The present invention relates to a hemorrhage reducing agent in cerebrovascular disorder containing a poly (ADP-ribose) polymerase inhibitor (PARP inhibitor). The PARP inhibitor provides an inhibitory effect of vascular endothelial cell disorder so that it may reduce hemorrhage in cerebrovascular disorder. In addition, the PARP inhibitor inhibits the hemorrhage that is concerned about in thrombolytic agent use by using together with a thrombolytic agent, and an effect of extending therapeutic time window of a thrombolytic agent may be further expected. Furthermore, the PARP inhibitor can be a safe hemorrhage reducing agent with fewer side effects because it does not affect the blood coagulation system and the fibrinolytic system.

Abstract: Fused pyridazine derivatives represented by formula (I) or pharmaceutically acceptable salts thereof (wherein each symbol has the meaning as defined in the specification.). Because of inhibiting poly(ADP-ribose)polymerase, the compounds represented by formula (I) are useful as preventives and/or remedies for various ischemic diseases (in brain, cord, heart, digestive tract, skeletal muscle, retina, etc.), inflammatory diseases (inflammatory bowel disease, multiple cerebrosclerosis, arthritis, etc.), neurodegenerative diseases (extrapyramidal disorder, Alzheimer's disease, muscular dystrophy, lumbar spinal canal stenosis, etc.), diabetes, shock, head trauma, renal failure, hyperalgesia, etc. Moreover, these compounds are useful as agents against retroviruses (HIV etc.), sensitizers in treating cancer and immunosuppressants.

Abstract: Fused pyridazine derivatives represented by formula (I) or pharmaceutically acceptable salts thereof (wherein each symbol has the meaning as defined in the specification.). Because of inhibiting poly(ADP-ribose)polymerase, the compounds represented by formula (I) are useful as preventives and/or remedies for various ischemic diseases (in brain, cord, heart, digestive tract, skeletal muscle, retina, etc.), inflammatory diseases (inflammatory bowel disease, multiple cerebrosclerosis, arthritis, etc.), neurodegenerative diseases (extrapyramidal disorder, Alzheimer's disease, muscular dystrophy, lumbar spinal canal stenosis, etc.), diabetes, shock, head trauma, renal failure, hyperalgesia, etc. Moreover, these compounds are useful as agents against retroviruses (HIV etc.), sensitizers in treating cancer and immunosuppressants.

Abstract: Fused pyridazine derivatives represented by formula (I) or pharmaceutically acceptable salts thereof (wherein each symbol has the meaning as defined in the specification.). Because of inhibiting poly(ADP-ribose)polymerase, the compounds represented by formula (I) are useful as preventives and/or remedies for various ischemic diseases (in brain, cord, heart, digestive tract, skeletal muscle, retina, etc.), inflammatory diseases (inflammatory bowel disease, multiple cerebrosclerosis, arthritis, etc.), neurodegenerative diseases (extrapyramidal disorder, Alzheimer's disease, muscular dystrophy, lumbar spinal canal stenosis, etc.), diabetes, shock, head trauma, renal failure, hyperalgesia, etc. Moreover, these compounds are useful as agents against retroviruses (HIV etc.), sensitizers in treating cancer and immunosuppressants.