RESUMO
GABA (gamma-aminobutyric acid) is the main inhibitory mediator in central nervous system. However, at early stages of ontogenesis, GABA has an excitatory effect on immature neurons. This review surveys modern concepts of the mechanisms of GABAergic excitation and physiological role of excitatory GABA in generation of patterns of network activity in developing brain.
Assuntos
Córtex Cerebral/crescimento & desenvolvimento , Rede Nervosa/crescimento & desenvolvimento , Ácido gama-Aminobutírico/fisiologia , Animais , Cloretos/fisiologia , Humanos , Interneurônios/fisiologia , Rede Nervosa/fisiologia , Receptores de GABA/fisiologiaRESUMO
The influence of essential fatty acids of mare's milk fat on the immunocompetent system and nonspecific resistance of male rats weighing 135-145 g was investigated after 6 weeks of feeding. Rats were fed with isocaloric purified diets containing 15% of test fat (in control--combination of lard and sunflower oil) which provide the ratio of omega-6/omega-3 fatty acids equal to 0.76. An increase of immune responsiveness and nonspecific resistance in the group fed with the diet with mare's milk fat on day 6 after a single immunization of the animals with 5% sheep erythrocyte suspension was noted.
Assuntos
Gorduras Insaturadas na Dieta/farmacologia , Ácidos Graxos Ômega-3/farmacologia , Ácidos Graxos Insaturados/farmacologia , Sistema Imunitário/efeitos dos fármacos , Leite , Animais , Ácidos Graxos Ômega-6 , Cavalos , Sistema Imunitário/imunologia , Imunidade Celular/efeitos dos fármacos , Imunidade Inata/efeitos dos fármacos , Imunização , Masculino , Ratos , Baço/efeitos dos fármacos , Baço/imunologia , Timo/efeitos dos fármacos , Timo/imunologia , Fatores de TempoRESUMO
Characteristics of spermatogenesis, morphometric changes in the Leydig's and Sertoli's cells, and fertility of albino rats exposed to various doses of 2.4-D were investigated. Chronic injection of the herbicide led to transitional sterility against pronounced disorders of spermatogenesis, hyperplasia of sertolicytes and predominance of low-active forms of the Leydig's cells. An assumption concerning possible role of altered gonadostat in genesis of the reproductive disorders is offered.