RESUMO
Studies of the protective actions of three doses of delta-sleep-inducing peptide (DSIP) given at different times before barochamber compression of animals to an oxygen tension of 0.7 MPa showed that the optimum DSIP dose is 12 micrograms/100 g. Intraperitoneal administration of this dose of DSIP delayed the onset of generalized convulsive activity by a factor of 2-2.5 in animals exposed to an oxygen tension of 0.7 MPa and promoted normalization of the sleep-walking cycle within 24 h after exposure to hyperbaric oxygen (HBO), by creating an optimal balance between excitatory and inhibitory amino acid neuromediators.
Assuntos
Anticonvulsivantes/farmacologia , Peptídeo Indutor do Sono Delta/farmacologia , Oxigenoterapia Hiperbárica/efeitos adversos , Convulsões/prevenção & controle , Animais , Câmaras de Exposição Atmosférica , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/metabolismo , Córtex Cerebral/fisiopatologia , Eletroencefalografia , Masculino , Neurotransmissores/metabolismo , Ratos , Convulsões/etiologia , Convulsões/metabolismo , Sono/efeitos dos fármacos , Vigília/efeitos dos fármacosRESUMO
Delta-sleep-inducing peptide (DSIP) exerted a protective effect against seizures, the effect depending on the DSIP ability to create an optimal ratio between inhibitory and excitatory amino acid neurotransmitters. Administration of the DSIP dramatically increased the contents of gamma-aminobutyric acid and homocarnosine while decreasing the glutamate and aspartate contents in the rat brain cortex.
Assuntos
Anticonvulsivantes/farmacologia , Peptídeo Indutor do Sono Delta/farmacologia , Oxigenoterapia Hiperbárica/efeitos adversos , Animais , Anticonvulsivantes/administração & dosagem , Câmaras de Exposição Atmosférica , Química Encefálica/efeitos dos fármacos , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/fisiologia , Peptídeo Indutor do Sono Delta/administração & dosagem , Relação Dose-Resposta a Droga , Eletrodos Implantados , Masculino , Ratos , Convulsões/etiologia , Convulsões/prevenção & controleRESUMO
The DSIP influence on the rat cortex, thalamic and hypothalamic adrenaline, noradrenaline, DOPA, dopamine and serotonin level under normal, hypokinetic stress condition (1 h in duration) and experimental audiogenic epilepsy was studied. It was found, that a single intraperitoneal DSIP injection (12 microns/100 g body weigh, 1 h before placing the animals into the stress condition) prevented spontaneous epileptic activity development due to creation of optimal ratio between monoamines in brain structures.
Assuntos
Peptídeo Indutor do Sono Delta/farmacologia , Epilepsia/metabolismo , Hipocinesia/metabolismo , Neurotransmissores/farmacologia , Estimulação Acústica/métodos , Animais , Química Encefálica/efeitos dos fármacos , Catecolaminas/análise , Córtex Cerebral/química , Córtex Cerebral/efeitos dos fármacos , Epilepsia/etiologia , Feminino , Hipocinesia/complicações , Hipotálamo/química , Hipotálamo/efeitos dos fármacos , Masculino , Ratos , Tálamo/química , Tálamo/efeitos dos fármacosRESUMO
Intracysternal putrescine before a session of hyperbaric oxygenation (0.7 MPa) was shown to be more effective in prolonging the latent period of onset of generalized convulsive activity than intraperitoneal delta-sleep-inducing peptide or its structural analogues ID-1 or ID-3. Biochemical studies indicated that putrescine was also more effective in preventing hyperbaric oxygenation-induced decreases in the levels of GABA and homocarnosine in the brain and the accumulation of lipid peroxidation products in the brain and serum.
Assuntos
Peptídeo Indutor do Sono Delta/farmacologia , Putrescina/farmacologia , Convulsões/tratamento farmacológico , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Carnosina/análogos & derivados , Carnosina/metabolismo , Peptídeo Indutor do Sono Delta/análogos & derivados , Oxigenoterapia Hiperbárica , Peroxidação de Lipídeos , Masculino , Ratos , Convulsões/metabolismo , Convulsões/fisiopatologia , Ácido gama-Aminobutírico/metabolismoAssuntos
Encéfalo/metabolismo , Carnosina/análogos & derivados , Estresse Fisiológico/metabolismo , Ácido gama-Aminobutírico/metabolismo , Animais , Encéfalo/efeitos dos fármacos , Química Encefálica/efeitos dos fármacos , Carnosina/efeitos dos fármacos , Carnosina/metabolismo , Peptídeo Indutor do Sono Delta/farmacologia , Oxigenoterapia Hiperbárica , Piracetam/farmacologia , Ratos , Restrição Física , Ácido gama-Aminobutírico/efeitos dos fármacosRESUMO
The homocarnosinase activity in different brain areas and kidneys of the normal rats and under different conditions of hyperbarooxygenation are determined. The highest activity of this enzyme is observed in cerebellum. The high homocarnosinase activity is typical of kidneys as well. The action of oxygen in a dose of 0.425 MPa for 60 min (in the absence of convulsions) increases the homocarnosinase activity in the cerebral hemispheres by 18.6%, in the midbrain by 18.6%, in midbrain and diencephalon--by 56.5%, and in the medulla oblongata--by 40.6%. The homocarnosinase activity in the cerebellum decreases by 16.7%, in kidneys--by 18.5%. At the convulsive stage of oxygen intoxication caused by the effect of 0.7 MPa dose of oxygen the homocarnosinase activity in cerebral hemispheres rises by 158.5%, in the midbrain and diencephalon--by 141.5%, in the medulla oblongata by--161.1%. Under the same conditions homocarnosinase activity in the cerebellum is unchanged as compared with the control.