Tachykinins and excitotoxicity in cerebellar granule cells.
ABSTRACT The tachykinins represent an important group of neuropeptides that are widely distributed both in the central and peripheral nervous system where they perform several functions connected with neuronal modulation, often in synergy with glutamate excitatory transmission. While a great deal of data is available on their distribution and many studies have been performed by molecular, biochemical, and immunohistochemical techniques, much less is known about their physiological role, in particular in the cerebellum. This review is an attempt to summarize the diverse evidence suggesting a role for tachykinins in cerebellar granule neurons.
Article: Neurotrophic effects of AMPA.[show abstract] [hide abstract]
ABSTRACT: AMPA-type glutamate receptors may transduce both neurotoxic and neurotrophic signals, basically depending on receptor subunit composition and on the extent of receptor activation. While a great deal of data are available on the mechanisms underlying the neurotoxic effects induced by AMPA receptor stimulation, much less is known about the molecular mechanisms responsible for their neurotrophic activities. This review describes the experimental evidences in favor of a neurotrophic effect of AMPA and compares the mechanisms identified and the signaling pathways involved with those relevant for the neurotrophic activities of other neurotrophins.The Cerebellum 02/2004; 3(1):2-10. · 2.60 Impact Factor
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ABSTRACT: Substance P was infused in the lateral ventricles of twenty Lewis rats for twenty days. On the twentieth day the animals were sacrificed and the cerebellar cortex was processed for electron microscopy. The ultrastructural morphometric analysis revealed that the Purkinje cell dendritic arborisation and the number of the synapses between the parallel fibres and the Purkinje cell dendritic spines were much higher than in control animals. Numerous unattached spines of the secondary and tertiary dendritic branches of the Purkinje cells were also seen in the molecular layer either free or surrounded by astrocytic sheath. The increased number of synapses between the Purkinje cell dendrites and the parallel fibres in the animals, which received substance P intraventricularly, in correlation to control animals, supports a neurotrophine-like activity of the substance P in the mammalian cerebellum, enforcing the pre-programmed capability of the Purkinje cells to develop new synaptic surfaces.International Journal of Neuroscience 02/2000; 101(1-4):89-107. · 1.22 Impact Factor