Correlations between substantia nigra (SN) dopamine (DA) cell activity and striatal extracellular DA were examined using simultaneous extracellular single-unit recordings and in vivo microdialysis performed in drug-naive rats and in rats treated repeatedly with haloperidol (HAL). Intact rats treated with HAL for 21-28 d exhibited significantly fewer active DA cells, indicating the presence of d...

To develop an in vitro model of methamphetamine (METH)-induced dopamine (DA) neurotoxicity, striatal synaptosomes were incubated at 37 degrees C with METH for different periods of time (10-80 min), washed once, then tested for DA transporter function at 37 degrees C. METH produced time- and dose-dependent reductions in the V(max) of DA uptake, without producing any change in K(m). Incubation of...

Hypoxic vasoconstriction (HV) is an intrinsic response of mammalian pulmonary and cyclostome aortic vascular smooth muscle. The present study examined the utilization of calcium during HV in dorsal aortas (DA) from sea lamprey and New Zealand hagfish. HV was temporally correlated with increased free cytosolic calcium (Ca2+c) in lamprey DA. Extracellular calcium (Ca2+o) did not contribute signif...

Using pharmacological approaches, we obtained evidence for the release of dopamine (DA) and its dopaminergic regulation in the guinea pig spinal cord. Electrical stimulation of the cord pieces increased the endogenous DA release and the efflux of [3H]dopamine [( 3H]DA) from tissues preloaded with [3H]DA. The evoked release of [3H]DA was current- and frequency-dependent and was prevented by tetr...

A influência da composição do eletrólito (ácido sulfúrico, ácido perclórico e suas misturas) sobre a cinética eletródica da reação de desprendimento de oxigênio (RDO) e a produção eletroquímica de ozônio (PEO) em eletrodo de β-PbO 2 , foi investigada empregando-se a espectroscopia de impedância eletroquímica e curvas de polarização quase-estacionárias. A análise dos espectros de impedância reve...

Resumen Este artículo pretende presentar la comprensión del mundo de la vida de la mujer que tiene el virus de la inmunodeficiencia humana en el cotidiano de la (im)posibilidad de amamantar. Se trata de una investigación cualitativa con abordaje fenomenológico, desarrollado en el Hospital Universitario de Santa Maria – Brasil. A partir de la entrevista fenomenológica, el análisis se dio conform...

Recent studies have proposed that glutamate corelease by mesostriatal dopamine (DA) neurons regulates behavioral activation by psychostimulants. How and when glutamate release by DA neurons might play this role remains unclear. Considering evidence for early expression of the type 2 vesicular glutamate transporter in mesencephalic DA neurons, we hypothesized that this cophenotype is particularl...

The putamen of the human striatum is a heterogeneous nucleus that contains the primary site of loss of dopamine (DA) in Parkinson's disease (PD). Furthermore, different functional domains of the putamen are heterogeneously susceptible to DA loss, and yet the dynamic regulation of extracellular DA concentration ([DA](o)) and comparison between domains has not been explored in the primate brain. ...

Dopamine (DA) is a key transmitter in the basal ganglia, yet DA transmission does not conform to several aspects of the classic synaptic doctrine. Axonal DA release occurs through vesicular exocytosis and is action potential- and Ca²⁺-dependent. However, in addition to axonal release, DA neurons in midbrain exhibit somatodendritic release by an incompletely understood, but apparently exocytotic...

1Professor Associado de Neuropsiquiatria do Curso de Medicina da Universidade Federal de Goiás (UFG). Programa de Pós-Graduação em Saúde Pública do Instituto de Patologia Tropical e Saúde Pública e Programa de Ciências da Saúde da UFG, Goiânia GO, Brasil; 2Médico Assistente do Hospital das Clínicas da UFG. Programa de Pós-Graduação em Ciências da Saúde da UFG, Goiânia GO, Brasil. Correspondence...