clinprost and Cerebrovascular-Disorders

The effects of TTC-909, the isocarbacyclin methyl ester clinprost (CAS 88931-51-5), incorporated into lipid microspheres, on ischemia-induced decrease in norepinephrine (NE) contents in stroke-prone spontaneously hypertensive rats (SHR-SP) with an occluded middle cerebral artery (MCA) were examined. Occluding of MCA led to infarction limited to the cerebral cortex and also a severe decrease in NE contents in peripheral regions of the infarction. TTC-909 was injected immediately after MCA occlusion, and then daily for 6 consecutive days. As TTC-909 in a dose of 200 ng/kg significantly (p < 0.05) prevented decreases in NE contents, TTC-909 may have cytoprotective effects on neuronal damage related to ischemia in humans.

Topics: Animals; Brain Chemistry; Cerebral Arteries; Cerebral Infarction; Cerebrovascular Disorders; Epoprostenol; Ischemic Attack, Transient; Male; Microspheres; Norepinephrine; Rats; Rats, Inbred SHR

The effects of the stable prostacyclin analogue TTC-909 on memory impairment in the water maze task and on neuronal damage were studied in rats with cerebral embolism induced by injecting polyvinyl acetate (PVA) into the right internal carotid artery and the ensuing embolism extending out into the right middle cerebral artery. Areas supplied by the lenticulostriate artery were most markedly damaged. In the water maze test, the PVA-embolized rats took longer to reach the platform than did the nontreated control rats. To some extent, repeated administrations of TTC-909 (200 ng/kg, IV) overcame this impairment in water maze learning in the rats. We assume that the vasodilating effects of TTC-909 maintain this blood supply to the ischemic area and that TTC-909 prevents the development of thrombosis around the PVA particles in the arterial capillaries, as a result of antiplatelet aggregative effects. These two mechanisms are likely to be involved in memory improvement. TTC-909 may prove effective for treating subjects with stroke and other cerebrovascular disorders.

Topics: Animals; Avoidance Learning; Brain Chemistry; Brain Edema; Cerebral Arteries; Cerebrovascular Circulation; Cerebrovascular Disorders; Epoprostenol; Glucose; Intracranial Embolism and Thrombosis; Male; Maze Learning; Memory Disorders; Neuroprotective Agents; Rats; Rats, Inbred SHR; Rats, Wistar

The prostacyclin analogue TTC-909 is incorporated in lipid microspheres and is chemically very stable. We examined the efficacy of TTC-909 on cerebral microcirculation following focal cerebral ischaemia. Focal cerebral ischaemia was produced by the occlusion of the distal middle cerebral artery in stroke-prone spontaneously hypertensive rats. Intravenous administration of TTC-909 (100 ng/kg/day) or vehicle was started 30 minutes after the occlusion and repeated for 7 days. On day 7, cerebral blood flow and blood-brain barrier permeability were measured autoradiographically. Brain oedema was estimated by the gravimetric method. The size of the infarction was calculated from area measurements on serial histologic sections. Treatment with TTC-909 resulted in significant improvement in regional blood flow in the ischaemic rim (p < 0.01) and the surrounding area (p < 0.05). With TTC-909 treatment, the increased permeability was significantly reduced in the ischaemic centre (p < 0.01) and rim (p < 0.05). A decrease in specific gravity in the ischaemic region and the remote non-ischaemic regions was prevented by the treatment (p < 0.01). We assumed that the efficacy of TTC-909 maintains the blood supply in the ischaemic area, improves disruption of the blood-brain barrier and prevents development of ischaemic oedema.

Topics: Animals; Blood-Brain Barrier; Brain; Brain Ischemia; Cerebrovascular Disorders; Epoprostenol; Hypertension; Infusions, Intravenous; Male; Microcirculation; Rats; Rats, Inbred SHR; Regional Blood Flow; Vasodilator Agents

The effects of stable PGI analogue TTC-909 on CBF and glucose metabolism was studied in the chronic stage of cerebral ischaemia produced by occluding the distal MCA in SHRSP. Administration of TTC-909 (100 ng/kg/day during 7 days) prevented the development of ischaemic oedema and improved secondary metabolic derangement coupled to flow in postischaemic tissues, particularly in the ischaemic rim.

Topics: Animals; Brain; Brain Ischemia; Cerebrovascular Circulation; Cerebrovascular Disorders; Disease Susceptibility; Epoprostenol; Glucose; Male; Rats; Rats, Inbred SHR; Tissue Distribution