TY - JOUR
T1 - Neuroglial interactions in a model of para-chlorophenylalanine-induced serotonin depletion
AU - Ramos, Alberto Javier
AU - Tagliaferro, Patricia
AU - López, Ester María
AU - Pecci Saavedra, Jorge
AU - Brusco, Alicia
PY - 2000/11/10
Y1 - 2000/11/10
N2 - Serotonin (5HT) is involved in the development and plasticity of the CNS through the release of S-100β, a glial trophic factor which stabilizes synapses and neuronal cytoskeleton and promotes neuronal development. S-100β is released from glial cells after activation of glial 5HT(1A) receptors. We present in this paper the effects upon neurons and glia of a 5HT depletion induced by 14 days of treatment with para-chlorophenylalanine (PCPA) in adult rats. S-100β, 5HT, 5HT-transporter (5HT-T) and neurofilaments (Nf-200 and Nf-68) expressions were studied by immunohistochemistry and image analysis in striatum, hippocampus, parietal and frontal cortex. Immediately after ending PCPA treatment we found increased intracellular S-100β immunoreactivity in glial cells, reduced 5HT immunolabelling, reduced density of 5HT-T, Nf-200 and Nf-68 fibers and morphological alterations in neuronal cytoskeleton. One week after PCPA treatment S-100β immunoreactivity decreased towards control levels, 5HT was normalized in dorsal raphe nucleus, but not in innervation areas; 5HT-T, Nf-200 and Nf-68 fiber densities increased but some neuronal cytoskeletal alterations were still present in striatum. Two weeks after PCPA treatment S-100β had returned to control levels in most studied regions; 5HT immunoreactivity was normalized, meanwhile 5HT-T, Nf-200 and Nf-68 fiber densities increased reaching values over the control level. We propose that S-100β could be accumulated in glial cells during the 5HT depletion period, to be released once 5HT levels have recovered. Neuronal cytoskeletal alterations and reduced fiber density may be the expression of decreased extracellular availability of S-100β. Conversely, increased 5HT-T, Nf-200 and Nf-68 expressions, once S-100β is normalized, may be the biological response to the growth factor release. (C) 2000 Elsevier Science B.V.
AB - Serotonin (5HT) is involved in the development and plasticity of the CNS through the release of S-100β, a glial trophic factor which stabilizes synapses and neuronal cytoskeleton and promotes neuronal development. S-100β is released from glial cells after activation of glial 5HT(1A) receptors. We present in this paper the effects upon neurons and glia of a 5HT depletion induced by 14 days of treatment with para-chlorophenylalanine (PCPA) in adult rats. S-100β, 5HT, 5HT-transporter (5HT-T) and neurofilaments (Nf-200 and Nf-68) expressions were studied by immunohistochemistry and image analysis in striatum, hippocampus, parietal and frontal cortex. Immediately after ending PCPA treatment we found increased intracellular S-100β immunoreactivity in glial cells, reduced 5HT immunolabelling, reduced density of 5HT-T, Nf-200 and Nf-68 fibers and morphological alterations in neuronal cytoskeleton. One week after PCPA treatment S-100β immunoreactivity decreased towards control levels, 5HT was normalized in dorsal raphe nucleus, but not in innervation areas; 5HT-T, Nf-200 and Nf-68 fiber densities increased but some neuronal cytoskeletal alterations were still present in striatum. Two weeks after PCPA treatment S-100β had returned to control levels in most studied regions; 5HT immunoreactivity was normalized, meanwhile 5HT-T, Nf-200 and Nf-68 fiber densities increased reaching values over the control level. We propose that S-100β could be accumulated in glial cells during the 5HT depletion period, to be released once 5HT levels have recovered. Neuronal cytoskeletal alterations and reduced fiber density may be the expression of decreased extracellular availability of S-100β. Conversely, increased 5HT-T, Nf-200 and Nf-68 expressions, once S-100β is normalized, may be the biological response to the growth factor release. (C) 2000 Elsevier Science B.V.
KW - Neurofilament
KW - Neurotrophic factor
KW - Parachlorophenylalanine
KW - S-100β
KW - Serotonin
KW - Serotonin transporter
UR - http://www.scopus.com/inward/record.url?scp=0034634538&partnerID=8YFLogxK
U2 - 10.1016/S0006-8993(00)02862-6
DO - 10.1016/S0006-8993(00)02862-6
M3 - Article
C2 - 11063982
AN - SCOPUS:0034634538
SN - 0006-8993
VL - 883
SP - 1
EP - 14
JO - Brain Research
JF - Brain Research
IS - 1
ER -