Assuntos
Encéfalo/efeitos dos fármacos , Cromatina/efeitos dos fármacos , Etimizol/farmacologia , Imidazóis/farmacologia , Memória/efeitos dos fármacos , Animais , Encéfalo/metabolismo , ATPases Transportadoras de Cálcio/metabolismo , Cromatina/metabolismo , Relação Dose-Resposta a Droga , Masculino , RNA/biossíntese , Ratos , Estimulação QuímicaRESUMO
A study was made of the RNA biosynthesis intensity in the brain cortex depending on the rate of the learning of the conditioned active avoidance and food reinforcement alteration responses in ethanol or water preferring rats placed in a complex maze. The level of the brain RNA biosynthesis in ethanol preferring rats was lower as compared with that in rats preferring water. In ethanol preferring rats, the rate of the learning of the conditioned active avoidance response was lower, whereas that of the learning of the alternation response was greater than in water preferring rats. The data are discussed in accordance with the concepts that disorders in the interaction of transmitter and genetic structures of brain cells form the basis of the behavior of ethanol preferring animals.
Assuntos
Consumo de Bebidas Alcoólicas , Comportamento Animal/efeitos dos fármacos , Comportamento de Ingestão de Líquido/fisiologia , Animais , Aprendizagem da Esquiva/efeitos dos fármacos , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/metabolismo , Condicionamento Clássico/efeitos dos fármacos , Masculino , RNA/biossíntese , RatosRESUMO
A single intraperitoneal injection of ethanol (2 g/kg) disturbed the learning and performance of one trial passive avoidance task and decreased (by 14 %) the level of RNA-synthesizing activity of brain cortical synaptosomes in rats. The data obtained are discussed in accordance with the hypothesis that ethanol affects synaptic transmission in the central nervous system.
Assuntos
Comportamento Animal/efeitos dos fármacos , Núcleo Celular/efeitos dos fármacos , Córtex Cerebral/efeitos dos fármacos , Etanol/administração & dosagem , RNA/biossíntese , Animais , Núcleo Celular/metabolismo , Córtex Cerebral/metabolismo , Condicionamento Clássico/efeitos dos fármacos , Relação Dose-Resposta a Droga , Masculino , Memória/efeitos dos fármacos , RatosRESUMO
Effects of ethimizole on the infraslow ascillations of the brain electrical activity were correlated with the pattern of its distribution within cellular structures. A negative wave of the infraslow activity was found to occur after the drug administration at the moment of its maximal inclusion into the two cellular fractions: the nuclei and the surface proteins of the endoplasmatic net. These structures seem to play part in changes of the central nervous system's functional state.
Assuntos
Córtex Cerebral/fisiologia , Animais , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/ultraestrutura , Etimizol/metabolismo , Etimizol/farmacologia , Masculino , Ratos , Ratos Endogâmicos , Frações Subcelulares/metabolismo , Fatores de TempoAssuntos
Membrana Celular/efeitos dos fármacos , Fenitoína/farmacologia , Animais , Transporte Biológico Ativo/efeitos dos fármacos , Cálcio/metabolismo , Membrana Celular/metabolismo , Permeabilidade da Membrana Celular/efeitos dos fármacos , Interações Medicamentosas , Ativação Enzimática/efeitos dos fármacos , Humanos , Canais Iônicos/efeitos dos fármacos , Canais Iônicos/metabolismo , Lipídeos de Membrana/metabolismo , Tecido Nervoso/efeitos dos fármacos , Tecido Nervoso/metabolismo , Nucleotídeos Cíclicos/metabolismo , Fenitoína/metabolismo , Sódio/metabolismoRESUMO
The dependence of the ATPase activity of skeletal muscle nuclei on divalent cations was studied. An addition of Ca2+ significantly increased the activity of nuclear ATPase. Mg2+ exerted an activating effect in the presence of 10(-5) M Ca2+ and an inhibiting effect in the presence of 2 x 10(-3) M Ca2+. Predominant localization of Ca-ATPase in the nucleoli and in the internal nuclear envelope was demonstrated by an electron microscopic histochemical technique. ATP increased the uptake of 45Ca by muscle nuclei; the optimal conditions for this incorporation were established. The changes in Ca-ATPase activities and in the ATP-dependent uptake of 45Ca induced by denervation and electric stimulation were found to be synchronous and unidirectional.
Assuntos
Adenosina Trifosfatases/metabolismo , ATPases Transportadoras de Cálcio/metabolismo , Cálcio/metabolismo , Núcleo Celular/enzimologia , Denervação Muscular , Músculos/fisiologia , Animais , Transporte Biológico Ativo , Nucléolo Celular/enzimologia , Núcleo Celular/ultraestrutura , Estimulação Elétrica , Ativação Enzimática , Magnésio/farmacologia , Masculino , Microscopia Eletrônica , Músculos/enzimologia , CoelhosRESUMO
Cell nuclei isolated from the cerebral cortex and hippocampus of Wistar and Krushinsky-Molodkina rats (the latter ones were examined both in quiet awake state and after audiogenic seizures) have different capacity to incorporate 3H-UTP. The levels of the label incorporation correlate with different calcium content in cell nuclei. Addition of exogenous calcium to nuclear suspension in the same concentration inhibits or activates 3H-UTP incorporation depending on the initial level of the nucleotide incorporation and on the endogenous calcium content. The data obtained allow the conclusion that the changes in calcium concentration in cell nuclei are one of the factors regulating RNA synthesis by brain cells in different functional states.
Assuntos
Cálcio/metabolismo , Córtex Cerebral/metabolismo , Hipocampo/metabolismo , RNA/biossíntese , Convulsões/metabolismo , Estimulação Acústica , Animais , Núcleo Celular/metabolismo , Ratos , Ratos Endogâmicos , Especificidade da EspécieRESUMO
Denervation of the rabbit gastrocnemius muscle is shown to result after 18 and 72 h in a decrease of Mg2+-, Ca2+-dependent and an increase of Mg+-dependent parts of nuclear ATPase activity, with the total level of the enzyme activity retained. 7 days later the total ATPase activity of nuclei decreases as well as the expense of its EGTA-dependent part. These changes correlate with those in the nuclear Ca total content. Indirect electrostimulation of the denervated muscle increase both the 7g2+-, Ca2+-dependent ATPase activity and the Ca content in nuclei. Tenotomy for 18 h does not change these parameters.
Assuntos
Adenosina Trifosfatases/metabolismo , Denervação Muscular , Músculos/enzimologia , Animais , Cálcio/farmacologia , Magnésio/farmacologia , Masculino , CoelhosRESUMO
The effects of Ca2+ on the RNA polymerase activity of the nuclei isolated from normal and denervated gastrocnemius muscles of the rabbit were studied. It was shown that 18 hrs after denervation the RNA synthesis in vitro, Ca2+ content and the Ca, Mg-ATPase activity of the nuclei are decreased. After addition of exogenous Ca2+ the incorporation of labelled UTP into the nuclei is stimulated in the denervated muscle and is inhibited in the control. Electrostimulation of the denervated muscle at the peripheral part of the sciatic nerve for 3 hrs increases both the RNA synthesis in the nuclei and the Ca2+ content, as well as the Ca, Mg-ATPase activity. Exogenous Ca2+ has an inhibitory effect on the nuclei of the stimulated muscle. The correlation established is indicative of participation of Ca2+ in the transmission of excitation in skeletal muscle sarcolemma to the processes occurring in nuclear structures.