L’inoculation intracranique de solutions de cuivre, de plomb et de mercure a démontré chez le rat, l'existence d'une sénsibilité tout-à-fait particulière des neurons des centres extrapyramidales envers le cuivre. On a, en effet, observé la chromatolyse central avec vacuolisation des neurones des plusieurs centres extrapyramidaux (globus pallidus, putamen, nucleus ruber... voir Tableau II) avec intégrité des autres structures neuronales, ce qui n'advient pas avec des autres métaux lourds. Nos observations...
The treatment of specimens of flatworms (Dugesia gonocephala s.l.) (Platyhelminthes, Turbellaria, Tricladida) with very diluted copper solutions shows initially an increase of dopamine-like activity and thereafter a complete paralysis of the same. The morphological substrate of such an activity consists in evident damages with copper-soaking of neurons. These data are in accordance with the high sensibility towards copper ions obtained in the nigro-striatal dopaminergic system of higher Vertebrates....
Motor patterns under different stimuli related to the functional role of the brain in Dugesia gonocephala s.l. The motor system of flatworms, with its dopaminergic-cholinergic interactions, seems to be very close to the extrapyramidal system of Mammalia (Man also). We have investigated the threshold dose of apomorphine and amphetamine, related to the histological regeneration of brain in different experimental conditions, i.e. cranial and caudal fragments of operated animals, unoperated or half-brain...
The Authors treated parenterally albino rats with organic salt and sodium azide; the latter in order to prevent the copper chelation by seric céruloplasmine and to maintain a high level of free hematic copper. Within 30 days such a treatment to a status spongiosus of white matter, Alzheimer's II glia production, focus of fat granule cells and proliferation of capillaries. As these lesions are peculiar to human Wilson disease the treatment in question may be considered as a valid experimental model....
A morphological and histochemical study focused on synaptic receptors of Dugesia gonocephala s.l. (Platheminthes, Turbellaria, Tricladida) has been conducted in 90 specimens. Special concern was given to the synaptic function of a reference zone closest to the eyes. The motor pattern of Dugesia was investigated administering different drugs acting on dopaminergic systems either stimulating (l-dopa, apomorphine, piribedil), or blocking (haloperidol), or depleting monoamine containing neurons like...
Behavioural and morphological observations have been conducted in specimens of flatworms (Dugesia gonocephala s.l.) treated with different ions such as zinc, lead, gold and silver. A copper-like activity of lead, gold and silver can be excluded; zinc-treated specimens show loss of motility comparable to the akinetic-end-phase described during copper exposure; the initial stage of copper-induced hyperkinesias probably depends upon a dopamine-like stimulation, specific to this ion.
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