Periaqueductal Grey Matter
Mostrando 1-10 de 10 artigos, teses e dissertações.
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1. ROLE OF DORSAL AND VENTRAL HIPPOCAMPUS ON CONDITIONED AND UNCONDITIONED FEAR ELICITED BY DORSAL PERIAQUEDUCTAL GREY MATTER ELECTRICAL STIMULATION IN RATS / PARTICIPAÇÃO DO HIPOCAMPO DORSAL E VENTRAL NAS REAÇÕES DE DEFESA PRODUZIDAS PELO CONDICIONAMENTO CONTEXTUAL DE MEDO E PELA ESTIMULAÇÃO ELÉTRICA DA MATÉRIA CINZENTA PERIAQUEDUTAL DORSAL
This study investigates the role of the hippocampus in both unconditioned and conditioned defense behavior by examining the effects of pre-training electrolytic lesions to the dorsal and ventral hippocampus in male rats exposed to two types of threat stimuli: electrical stimulation of the DPAG and footshock. Our results indicate that ventral and dorsal lesio
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 30/03/2012
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2. O bloqueio dos receptores 5-HT2 da substância cinzenta periaquedutal suprime o efeito ansiolítico resultante do antagonismo dos receptores 5-HT1A do núcleo mediano da rafe em camundongos / Blockade of 5-HT2 receptors in the periaqueductal grey matter (PAG) abolishes the anxiolytic-like effect of 5-HT1A receptor antagonism in the median raphé nucleus in mice. 2011.
Várias evidências apontam o envolvimento de neurônios serotoninérgicos do núcleo mediano da rafe (NMnR) na ansiedade. Sabe-se que o bloqueio dos autorreceptores somatodendríticos dos núcleos da rafe aumenta a taxa de disparo dos neurônios serotoninérgicos, promovendo a liberação de serotonina em sítios pós-sinápticos como amígdala, hipocampo e
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 15/12/2011
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3. Avaliação do papel dos receptores 5-HT3 da substância cinzenta periaquedutal de camundongos submetidos ao labirinto em cruz elevado
A exposição de animais a situações aversivas, tais como o labirinto em cruz elevado (LCE), ativa vias serotoninérgicas com projeções para estruturas envolvidas no sistema de defesa tais como, amídala, septo, hipotálamo, hipocampo e substância cinzenta periaquedutal (SCP), produzindo alterações comportamentais que podem ser caracterizadas como ans
Publicado em: 2009
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4. Morpho-quantitative analysis of nuclear inclusions in periaqueductal grey matter neurons in the cat.
The morpho-quantitative analysis carried out in the neuronal population of the periaqueductal grey matter of the cat has shown that nuclear inclusions are mainly of the filamentous type and that they are distributed predominantly in the external region, i.e. in the part of the periaqueductal grey matter situated furthest from the cerebral aqueduct, where 30%
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5. A search for brain stem cell groups integrating the defence reaction in the rat.
The defence areas of the rat brain stem have been extensively explored using electrical and chemical stimulation in an attempt to locate the regions containing the perikarya of neurones which may initiate or integrate the visceral and behavioural components of the defence reaction. In rats anaesthetized with alphaxalone-alphadolone, a cannula electrode was u
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6. Facilitation of the arterial baroreflex by the ventrolateral part of the midbrain periaqueductal grey matter in rats.
1. The effects of stimulation of the ventrolateral part of the midbrain periaqueductal grey matter (PAG) on the arterial baroreflex were investigated in urethane-chloralose anaesthetized and artificially ventilated rats. 2. Both electrical and chemical stimulation of the ventrolateral PAG provoked hypotension, vagal bradycardia and marked facilitation of bar
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7. Facilitation of the arterial baroreflex by the preoptic area in anaesthetized rats.
1. Activation of cell bodies in the ventrolateral part of the midbrain periaqueductal grey matter (PAG) facilitates the arterial baroreflex via the nucleus raphe magnus. The facilitatory effects of stimulation within the hypothalamus on the arterial baroreflex and their relation to the PAG and nucleus raphe magnus were studied in urethane- and chloralose-ana
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8. Effect of midbrain stimulations on thermoregulatory vasomotor responses in rats.
1. Efferent projections eliciting vasodilatation when the preoptic area is warmed were investigated by monitoring tail vasomotor responses of ketamine-anaesthetized rats when brain areas were stimulated electrically (0.2 mA, 200 microseconds, 30 Hz) or with the excitatory amino acid D,L-homocysteic acid (1 mM, 0.3 microliter). 2. Both stimulations elicited v
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9. Properties and ionic basis of the action potentials in the periaqueductal grey neurones of the guinea-pig.
1. Action potentials of neurones of the ventral part of the guinea-pig periaqueductal grey (PAG) were studied by intracellular recording in a mesencephalic slice preparation maintained in vitro. 2. Fast spikes spontaneously fired last 2.8 +/- 0.6 ms (mean +/- S.D.) and have an amplitude of 72.3 +/- 5.3 mV (n = 28). The neurones could be antidromically activa
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10. Supraspinal morphine and descending inhibitions acting on the dorsal horn of the rat.
1. Recordings were made from thirty-nine convergent neurones in the lumbar enlargement of the rat spinal cord. These neurones were activated by both innocuous and noxious stimuli applied to their excitatory receptive fields located on the extremity of the ipsilateral hind paw. Transcutaneous application of suprathreshold 2 ms square-wave pulses to the centre