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J Glowinski

Publications and source records attributed to J Glowinski.

At least 397 records · Page 22Linked to original sources
PubMed1979

Topographical distribution of substance P in the cat substantia nigra.

The substance P (SP) content in cat substantia nigra (SN) was estimated by radioimmunoassay in microdiscs punched on successive frontal sections. Only slight differences were seen in the regional distribution of SP within the SN. The highest content was found in the pars reticulata (20.7 pmol/mg protein) which was two times higher than in the pars compacta and pars lateralis. Identical results were found in the right and left part of the SN. Out of this area, as pedunculus cerebri and zona incerta, very low concentrations were detected.

Animals↗
PubMed1979

Increased utilization of dopamine in the nucleus accumbens but not in the cerebral cortex after dorsal raphe lesion in the rat.

Dihydroxyphenylacetic acid (DOPAC) and dopamine (DA) levels were estimated in the frontal cortex, the nucleus accumbens and the striatum of the rat after electrolytical lesion of the dorsal raphe nucleus. The efficiency of this lesion was tested by measuring the decline in serotonin (5-HT) levels in the striatum. 5-HT levels were reduced by 90% when compared to those of sham-operated rats 11 days after the lesion. As revealed both by the increase in DOPAC levels and in the DOPAC/DA ratio, the rate of DA utilization was markedly increased in the nucleus accumbens, slightly enhanced in the striatum and in contrast remained unaffected in the frontal cerebral cortex 4 days after the lesion. Changes in DOPAC levels in the nucleus accumbens were also seen 11 and 30 days after the lesion but they were less pronounced than those observed at 4 days. These results suggest that neurons originating from the dorsal raphe and projecting to the ventro-tegmental area are regulating the activity of the meso-nucleus accumbens dopaminergic neurons but not that of the meso-cortical dopaminergic neurons.

3,4-Dihydroxyphenylacetic Acid↗
PubMed1979

In vivo release of substance P in the cat substantia nigra.

Push-pull cannuale were implanted into the substantia nigra (SN) and the caudate nucleus (CN) of the cat to study the in vivo release of substance P (SP), using a radioimmunoassay and high pressure liquid chromatography (HPLC) analysis. The spontaneous release of SP could be detected in the SN and the CN. Potassium (50 mM) locally applied stimulated SP release in both structures. Furthermore an important evoked release of SP was observed in the SN during depolarization of striato-nigral SP fibers with potassium (50 mM) applied in the CN.

Animals↗
PubMed1979

The presynaptic stimulating effect of acetylcholine on dopamine release is suppressed during activation of nigro-striatal dopaminergic neurons in the cat.

Acetylcholine (ACh) (10(-5) M) in the presence of eserine (2 . 10(-4) M) stimulated the release of [3H]dopamine (DA) continuously formed from [3H]tyrosine, when delivered to a push-pull cannula implanted in the left caudate nucleus of halothane anaesthetized cats. This effect was transient and followed by a second increase in [3H]DA release after removal of ACh and eserine. These changes in [3H]DA release during and after ACh application were no longer seen during activation of the dopaminergic neurons by continuous delivery of substance P to the ipsilateral substantia nigra (SN). These results indicate that the presynaptic regulation of DA release by ACh is dependent on the rate of firing of nigro-striatal dopaminergic neurons.

Acetylcholine↗
PubMed1979

In vitro maturation of mesencephalic dopaminergic neurons from mouse embryos is enhanced in presence of their striatal target cells.

Long-term survival of mesencephalic and striatal cells from mouse embryos in dissociated primary cultures is described. Catecholaminergic neurons in mesencephalic culutres were identified histochemically and by measuring [3H]dopamine uptake and synthesis from [3H]tyrosine. According to experiments using specific inhibitors of catecholamine uptake, at least two-thirds of the catecholaminergic neurons are dopaminergic. These neurons differentiated whether or not striatal target cells were present, but striatal cells stimulated the development of the dopaminergic neurons. [3H]Dopamine uptake was increased by at least 2-fold regardless of the age of the cocultures (4-15 days). Enhanced [3H]dopamine synthesis was also observed (at least 2-fold) at later times (12-15 days).

Animals↗
PubMed1979

Chronic methods to study the release of catecholamines from the neostriatum in nonanaesthetized monkeys (Macaca mulatta).

The present report describes two methods allowing the chronic collection of catecholamine (CA) released from the neostriatum in the nonanaesthetized monkey (Macaca mulatta). In both methods the monkeys were placed in a restraining chair. Indwelling electrodes allowed the correlation of behavioural observations with polygraphic recordings. The first method uses a special superfusing cup permanently implanted on the lateral surface of the caudate nucleus, which permits the demonstration of spontaneous and D-amphetamine-induced release of (3H)-dopamine (DA) newly synthesized from L-(3,5-3H)-tyrosine over a period of six days. In the second method the collection of unlabelled CA is carried out by a localized ventricular perfusion. A radio-enzymatic estimation enabled the measurement of unlabelled DA and noradrenaline. With this second method the animals were kept for 25 to 30 days.

Amphetamine↗
PubMed1979

Role of various amino acids on the modulation of dopamine release from nigro-striatal dopaminergic neurones.

The effects of various transmitter amino-acids on the striatal release of 3H-dopamine (3H-DA) were investigated both in vivo in cat and in vitro in rat striatal slices. When applied to the substantia nigra of the anaesthetized cat by means of a push-pull cannula, GABA induced an increase followed by a transient decrease of 3H-DA release in the ipsilateral caudate nucleus; glycine reduced 3H-DA release under similar experimental conditions. When added to the superfusion medium of rat striatal slices, GABA, glutamate and glycine increased the release of the newly synthetized 3H-DA, suggesting that these amino-acids are also directly or indirectly involved in the presynaptic modulation of striatal DA release.

Animals↗