ABSTRACT
We studied antiepileptic effects of cortexin administered in doses 0,015, 0,15 and 1,0 mg/kg intraperitoneally in solution or intranasally in the complex with nanoparticles in a model of acute and chronic convulsions in rats induced by pentylenetetrazole. In the model of epileptic status, the long-term preliminary administration of cortexin had no effect on convulsions while in the model of chronic convulsions (temporal epilepsy), cortexin had a marked dose-dependent antiepileptic effect. The influence of cortexin on neuroplasticity and its clinical potential are discussed.
Subject(s)
Anticonvulsants/administration & dosage , Peptides/administration & dosage , Seizures/drug therapy , Administration, Intranasal , Animals , Disease Models, Animal , Intercellular Signaling Peptides and Proteins , Intraabdominal Infections , Male , Rats , Rats, WistarABSTRACT
Impairment of cognitive functions, particularly long-term (episodic) and working memory, is one of the earliest prognostic symptoms of Alzheimer's disease, both cognitive impairment and neurodegeneration being mediated by amyloid-beta neurotoxicity. Effects of intracerebroventricular administration of amyloid-beta peptide (25-35) [A beta(25-35)] to rats on the retention of previously learned task in an 8-armed radial maze was studied. A beta(25-35) was injected bilaterally, at doses of 15 or 30 nmol/rat, 7 days after the preliminary learning. The performance in the maze was tested 60 days after the surgery. A beta(25-35) impaired the short-term memory, with no significant effect on the long-term memory. No dose dependence could be demonstrated.
Subject(s)
Amyloid beta-Peptides/toxicity , Behavior, Animal/drug effects , Maze Learning/drug effects , Adaptation, Psychological , Amyloid beta-Peptides/administration & dosage , Animals , Injections, Intraventricular , Male , Memory, Short-Term/drug effects , Rats , Rats, Wistar , Time FactorsSubject(s)
Amyloid beta-Peptides/pharmacology , Brain/drug effects , Lipid Peroxidation/drug effects , Peptide Fragments/pharmacology , Amyloid beta-Peptides/administration & dosage , Animals , Blood , Brain/metabolism , Injections, Intraventricular , Male , Peptide Fragments/administration & dosage , Rats , Rats, WistarABSTRACT
Within 8 days of a 10-min cardiac arrest, accumulation of material reacting with 2-thiobarbituric acid was revealed in the hippocampus (74%) and cerebellum (47%) of male Wistar rats. Oxidative stress was accompanied by a twofold decrease of the nitric oxide synthase activity in the brain tissue. In vitro experiments showed a dose-dependent decrease of nitric oxide synthase activity in the brain homogenates as a result of the oxidative stress induced by hydrogen peroxide or sodium hypochlorite. The findings suggest that the oxidative stress may decrease nitric oxide synthase activity as a result of direct effects of the active oxygen on the enzyme.