Biomaterial Database

Pretreatment of transient focal cerebral ischemia in rats with the calcium antagonist AT877. 1994

M Ohtaki, and B Tranmer

Department of Clinical Neurosciences, University of Calgary, Alberta, Canada.

OBJECTIVE The efficacy of pretreatment with the recently developed intracellular calcium antagonist AT877 against transient focal cerebral ischemia was investigated in rats subjected to middle cerebral artery occlusion and reperfusion using the endovascular suture method. METHODS Halothane-induced moderate hypotension (60 mm Hg) was used during 100 minutes of temporary middle cerebral artery occlusion. In the treated animals (n = 10), an intravenous infusion of AT877 (0.03 mg/kg per minute) was initiated 30 minutes before the ischemic event and continued during the ischemic period. The control rats (n = 10) received physiological saline in a similar fashion. Local cerebral blood flow was measured by the hydrogen clearance technique. Neurological examinations were performed daily during the 48-hour observation period, and infarct size was assessed by triphenyltetrazolium chloride staining. RESULTS A continuous infusion of AT877 significantly improved local cerebral blood flow during ischemia. The treated animals showed a better neurological outcome after a 24-hour observation period, and a significant reduction in ischemic brain injury resulted in both the neocortex (149 +/- 20 versus 41 +/- 14 mm3, P < .01) and the striatum (80 +/- 5 versus 46 +/- 8 mm3, P < .05). The size of the neocortical infarct was reduced, with increasing mean ischemic cerebral blood flow in the control and treated animals (r = .923, P = .0001). CONCLUSIONS AT877 pretreatment was effective in preventing brain injury during transient focal cerebral ischemia and improving neurological status. This beneficial effect seems to be mediated, in part, by its primary action of increasing cerebral blood flow.

UI	MeSH Term	Description	Entries
D007262	Infusions, Intravenous	The long-term (minutes to hours) administration of a fluid into the vein through venipuncture, either by letting the fluid flow by gravity or by pumping it.	Drip Infusions,Intravenous Drip,Intravenous Infusions,Drip Infusion,Drip, Intravenous,Infusion, Drip,Infusion, Intravenous,Infusions, Drip,Intravenous Infusion
D007546	Isoquinolines	A group of compounds with the heterocyclic ring structure of benzo(c)pyridine. The ring structure is characteristic of the group of opium alkaloids such as papaverine. (From Stedman, 25th ed)
D008297	Male		Males
D009460	Neurologic Examination	Assessment of sensory and motor responses and reflexes that is used to determine impairment of the nervous system.	Examination, Neurologic,Neurological Examination,Examination, Neurological,Examinations, Neurologic,Examinations, Neurological,Neurologic Examinations,Neurological Examinations
D010291	Paresis	A general term referring to a mild to moderate degree of muscular weakness, occasionally used as a synonym for PARALYSIS (severe or complete loss of motor function). In the older literature, paresis often referred specifically to paretic neurosyphilis (see NEUROSYPHILIS). "General paresis" and "general paralysis" may still carry that connotation. Bilateral lower extremity paresis is referred to as PARAPARESIS.	Hemiparesis,Muscle Paresis,Brachial Paresis,Crural Paresis,Lower Extremity Paresis,Monoparesis,Muscular Paresis,Upper Extremity Paresis,Brachial Pareses,Crural Pareses,Extremity Pareses, Lower,Extremity Pareses, Upper,Extremity Paresis, Lower,Extremity Paresis, Upper,Hemipareses,Lower Extremity Pareses,Monopareses,Muscle Pareses,Muscular Pareses,Pareses,Pareses, Brachial,Pareses, Crural,Pareses, Lower Extremity,Pareses, Muscle,Pareses, Muscular,Pareses, Upper Extremity,Paresis, Brachial,Paresis, Crural,Paresis, Lower Extremity,Paresis, Muscle,Paresis, Muscular,Paresis, Upper Extremity,Upper Extremity Pareses
D011292	Premedication	Preliminary administration of a drug preceding a diagnostic, therapeutic, or surgical procedure. The commonest types of premedication are antibiotics (ANTIBIOTIC PROPHYLAXIS) and anti-anxiety agents. It does not include PREANESTHETIC MEDICATION.	Premedications
D001794	Blood Pressure	PRESSURE of the BLOOD on the ARTERIES and other BLOOD VESSELS.	Systolic Pressure,Diastolic Pressure,Pulse Pressure,Pressure, Blood,Pressure, Diastolic,Pressure, Pulse,Pressure, Systolic,Pressures, Systolic
D002118	Calcium	A basic element found in nearly all tissues. It is a member of the alkaline earth family of metals with the atomic symbol Ca, atomic number 20, and atomic weight 40. Calcium is the most abundant mineral in the body and combines with phosphorus to form calcium phosphate in the bones and teeth. It is essential for the normal functioning of nerves and muscles and plays a role in blood coagulation (as factor IV) and in many enzymatic processes.	Coagulation Factor IV,Factor IV,Blood Coagulation Factor IV,Calcium-40,Calcium 40,Factor IV, Coagulation
D002536	Cerebral Arteries	The arterial blood vessels supplying the CEREBRUM.	Arteries, Cerebral,Artery, Cerebral,Cerebral Artery
D002540	Cerebral Cortex	The thin layer of GRAY MATTER on the surface of the CEREBRAL HEMISPHERES that develops from the TELENCEPHALON and folds into gyri and sulci. It reaches its highest development in humans and is responsible for intellectual faculties and higher mental functions.	Allocortex,Archipallium,Cortex Cerebri,Cortical Plate,Paleocortex,Periallocortex,Allocortices,Archipalliums,Cerebral Cortices,Cortex Cerebrus,Cortex, Cerebral,Cortical Plates,Paleocortices,Periallocortices,Plate, Cortical