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Query: UNIPROT:P20366 (
substance P
)
21,176
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
It is unknown whether adult dorsal root ganglion (DRG) neurons require trophic factors for their survival and maintenance of neuropeptide phenotypes. We have established and characterized neuron-enriched cultures of adult rat DRGs and investigated their responses to nerve growth factor (NGF), ciliary neuronotrophic factor (CNTF), pig brain extract (PBE, crude fraction of brain-derived neuronotrophic factor,
BDNF
), and laminin (LN). DRGs were dissected from levels C1 through L6 and dissociated and freed from myelin fragments and most satellite (S-100-immunoreactive) cells by centrifugation on Percoll and preplating. The enriched neurons, characterized by their morphology and immunoreactivity for neuron-specific enolase, constituted a population representative of the in vivo situation with regard to expression of
substance P
(SP), somatostatin (SOM), and cholecystokinin-8 (CCK) immunoreactivities. In the absence of trophic factors and using polyornithine (PORN) as a substratum, 60-70% of the neurons present initially (0.5 days) had died after 7 days. LN as a substratum did not prevent a 30% loss of neurons up to day 4.5, but it subsequently maintained DRG neurons at a plateau. This behavior might reflect a cotrophic effect of LN and factors provided by non-neuronal cells, whose proliferation between 4.5 and 7 days could not be prevented by addition of mitotic inhibitors of gamma-irradiation. CNTF, but not NGF, slightly enhanced survival at 7 days on either PORN or LN. No neuronal losses were found in non-enriched cultures or when enriched neurons were supplemented with PBE, indicating that non-neuronal cells and PBE provide factor(s) essential for adult DRG neuron survival. Proportions of SP-, SOM-, and CCK-immunoreactive cells were unaltered under any experimental condition, with the exception of a numerical decline in SP cells in 7-day cultures with LN, but not PORN, as the substratum. Our data, considered in the context of recent in vivo and vitro studies, suggest that a combination of trophic factors or an unidentified factor, rather than the established molecules NGF, CNTF, and
BDNF
, which address embryonic and neonatal DRG neurons, are required for the in vitro maintenance of adult DRG neurons.
...
PMID:Neuron-enriched cultures of adult rat dorsal root ganglia: establishment, characterization, survival, and neuropeptide expression in response to trophic factors. 244 41
Neuronal precursor cells present in dorsal root ganglia (DRG) during early development have been previously shown to differentiate in vitro to neurons, as characterized by morphology, cell surface antigens, and electrophysiological properties (H. Rohrer, S. Henke-Fahle, T. El-Sharkawy, H. D. Lux, and H. Thoenen, 1985, Embo J. 4, 1709-1714). In the present study the conditions necessary for the initial differentiation and long-term survival of these cells were established, and the neurotransmitter phenotype of the newly differentiated neurons was analyzed. Neuronal precursor cells isolated from chick DRG at Embryonic Day 6 (E6) were found to require the presence of a polyornithine substrate coated with either laminin or fibronectin for initial neurite production and long-term survival. Neurons were unable to develop on polyornithine alone or on polyornithine coated with BSA. The survival and neurite outgrowth from neuronal precursor cells was not affected by the presence of nerve growth factor (NGF) during the first 9 hr in culture. NGF also had no effect on the proportion of cells expressing the neuron-specific Q211 antigen. However, after this initial differentiation period the neurons did require the presence of a survival factor. The neurons could be maintained for at least 6 days in culture both in the presence of NGF and in the presence of
brain-derived neurotrophic factor
(
BDNF
). At saturating concentrations of both survival factors no additive effects could be observed, indicating a complete overlap of NGF- and
BDNF
-responsiveness. Although the same proportion of cells survived with either NGF or
BDNF
during the first 3 days in culture, survival decreased in the presence of
BDNF
but not in the presence of NGF during the following 3 days in culture. The loss of
BDNF
responsiveness in vitro was also observed in vivo. After 6 days in culture about 70% of the neurons expressed
substance P
immunoreactivity, and approximately the same proportion was positive for myelin-associated glycoprotein immunoreactivity. The neurons did not express properties of adrenergic neurons such as tyrosine hydroxylase immunoreactivity or norepinephrine uptake. These findings indicate that the neuronal precursor cells from E6 DRG acquire the same characteristics in vitro as in their normal in vivo environment.
...
PMID:Neuronal precursor cells in chick dorsal root ganglia: differentiation and survival in vitro. 245 Jul 97
In contrast to developing sensory neurons, the survival of adult rat dorsal root ganglion neurons in pure neuronal culture is not dependent on specific neurotrophic factors such as nerve growth factor or
brain-derived neurotrophic factor
[Lindsay R. M. (1988) J. Neurosci. 8, 2394-2405]. In the present study we have examined possible modulatory effects of nerve growth factor on the neuropeptide content of sub-populations of adult rat dorsal root ganglion neurons in vitro. During the first 1-2 days in culture the neuropeptides
substance P
and calcitonin gene-related peptide could be detected by immunofluorescence staining in cultures grown in the presence or absence of nerve growth factor, but at longer times in nerve growth factor-deprived cultures there was loss of immunoreactive staining for both peptides. In the presence of nerve growth factor, however, the percentage of
substance P
- and calcitonin gene-related peptide-immunoreactive neurons remained relatively constant, for at least 14 days, at levels that were similar to the percentage of such peptide-containing neurons found in sections of adult rat dorsal root ganglia. Quantitation by radioimmunoassay of the levels of
substance P
and calcitonin gene-related peptide in cultures grown in the presence or absence of nerve growth factor agreed with the qualitative observations obtained by immunofluorescence: 10-15-fold higher levels of
substance P
and calcitonin gene-related peptide were found in cultures grown with nerve growth factor for 18 days, as compared to nerve growth factor-deprived cultures. In nerve growth factor-treated cultures increased levels of
substance P
and calcitonin gene-related peptide were observed within 3-6 days in vitro, and further steady increases in the levels of both peptides were found up to 18 days. A low basal level of both peptides could always be detected, even in the presence of an excess of antibodies to nerve growth factor. Up-regulation of the synthesis of
substance P
and calcitonin gene-related peptide did not depend on nerve growth factor being present at the initiation of the cultures, as elevated levels of both peptides could be induced in cultures even after up to 10 days' prior deprivation of nerve growth factor. Removal of nerve growth factor from the cultures resulted in reduced levels of peptide within 3 days.(ABSTRACT TRUNCATED AT 400 WORDS)
...
PMID:Neuropeptide expression in cultures of adult sensory neurons: modulation of substance P and calcitonin gene-related peptide levels by nerve growth factor. 248 Dec 45
Rats with streptozotocin-induced diabetes of 4 to 6 weeks duration showed a depletion of both
substance P
(P < 0.01) and calcitonin gene-related peptide (P < 0.01) in the sciatic nerve. Since expression of both peptides is sensitive to nerve growth factor (NGF) in vitro we examined the effect of treatment of diabetic rats with NGF, which significantly increased the levels of both peptides in treated diabetic animals (P < 0.01 for both). Treatment of non-diabetic rats with a similar NGF regime raised the mean peptide levels to a value similar to that seen in treated diabetic rats but the change was not statistically significant. In vehicle-treated diabetic rats the depletions of sciatic nerve neuropeptides were accompanied by a significant (P < 0.05) reduction in the level of CGRP mRNA in the 4th and 5th lumbar dorsal root ganglia, this was accompanied by an analogous reduction in the mRNA for gamma-
preprotachykinin
A (gamma-PPT), which did not attain statistical significance. Treatment of diabetic rats with NGF also prevented the deficits in the levels of CGRP and gamma-PPT mRNA in the lumbar dorsal root ganglia (P < 0.05). Treatment of other diabetic rats with the related neurotrophin,
brain-derived neurotrophic factor
(
BDNF
), had no effect on the levels of
substance P
and calcitonin gene-related peptide in the sciatic nerve.
...
PMID:Expression of neuropeptides in experimental diabetes; effects of treatment with nerve growth factor or brain-derived neurotrophic factor. 751 41
Adult rat dorsal root ganglion sensory neurons in culture require nerve growth factor for synthesis of
substance P
and calcitonin gene-related peptide but express vasoactive intestinal peptide independently of nerve growth factor. In contrast, the same neurons from newborn rats do not express detectable vasoactive intestinal polypeptide when cultured with nerve growth factor. To further explore the mechanisms regulating neuropeptide expression in these cells, I compared the effects of nerve growth factor,
brain-derived neurotrophic factor
, neurotrophin-3, ciliary neurotrophic factor and leukaemia inhibitory factor on
substance P
, calcitonin gene-related peptide, vasoactive intestinal polypeptide and somatostatin expression in rat dorsal root ganglion cultures. As with neurons from adult animals, newborn rat sensory neurons required nerve growth factor for synthesis of
substance P
and calcitonin gene-related peptide. This effect was independent of neuronal survival since most neurons capable of expressing these peptides appeared to survive without added neurotrophic factors. Neurons surviving in the absence of nerve growth factor also expressed vasoactive intestinal polypeptide, suggesting that nerve growth factor suppresses vasoactive intestinal polypeptide expression in immature neurons. However, nerve growth factor withdrawal after eight days' culture failed to cause vasoactive intestinal polypeptide induction which therefore appears to depend on other factors also. Neither ciliary neurotrophic factor nor leukaemia inhibitory factor affected peptide levels when used alone, but both inhibited nerve growth factor-stimulated expression of
substance P
and calcitonin gene-related peptide in adult rat neurons. They also stimulated vasoactive intestinal polypeptide expression in newborn rat neurons in the presence of nerve growth factor but not to such high levels as those seen under conditions of nerve growth factor deprivation. Neither
brain-derived neurotrophic factor
nor neurotrophin-3 affected peptide expression significantly. Somatostatin was defected in adult rat neurons, but was unaffected by neurotrophic factors. No somatostatin was detected in newborn rat neurons. These results suggest that in immature animals at least, the increased expression of vasoactive intestinal polypeptide seen in sensory neurons following peripheral nerve injury in vivo, could result from deprivation of target-derived nerve growth factor in combination with increased availability of ciliary neurotrophic factor or leukaemia inhibitory factor from the injured nerve.
...
PMID:Neuropeptide expression by newborn and adult rat sensory neurons in culture: effects of nerve growth factor and other neurotrophic factors. 751 8
The effects of NGF,
BDNF
, NT-3,
BDNF
plus NT-3 and LIF on
substance P
(SP) mRNA levels were analysed in axotomized dorsal root ganglia (DRGs) in vivo by quantitative in situ hybridization. The growth factors were applied on to the transected sciatic nerve. SP mRNA levels were decreased significantly 3 days after axotomy. NGF (1 microgram) fully counteracted the down-regulation of SP mRNA. Neither
BDNF
(10 micrograms) nor NT-3 (10 micrograms) alone had any effect. However, co-administration of
BDNF
together with NT-3 (10 micrograms) distinctly reversed the decrease in SP mRNA. A similar effect was seen with a high (1.5 micrograms) but not a low dose of LIF (0.15 microgram). Our data suggest that the present method of delivering growth factors to the transected sciatic nerve is a valid way to study in vivo effects of growth factors on peptide expression in DRGs. Moreover, SP expression is regulated by several growth factors in vivo such as NGF,
BDNF
plus NT-3 as well as the neuroimmune factor LIF.
...
PMID:Effect of growth factors on substance P mRNA expression in axotomized dorsal root ganglia. 754 54
Disruption of dopaminergic neurotransmission in the striatum by neurotoxic lesions of the substantia nigra leads to increases in glutamic acid decarboxylase and proenkephalin messenger RNA expression, and to decreases in preprotackykinin (the precursor molecule for
substance P
) messenger RNA expression in the two populations of striatal medium-sized spiny projection neurons. These cells also express TrkB, the neurotrophin receptor for
brain-derived neurotrophic factor
and neurotrophin 4/5, and TrkC, the receptor for neurotrophin-3. Since there is some indication that exogenous
brain-derived neurotrophic factor
can exert neuromodulatory effects in the basal ganglia, we studied the effects of repeated intrastriatal injections of the four members of the neurotrophin family of neural growth factors, nerve growth factor,
brain-derived neurotrophic factor
, neurotrophin-3, and neurotrophin-4/5 on the expression of striatal neurotransmitter-related genes in the unilaterally 6-hydroxydopamine-lesioned rat using in situ hybridization histochemistry. We found that 4 micrograms/day of
brain-derived neurotrophic factor
or neurotrophin-4/5 when injected intrastriatally for eight consecutive days led to a normalization of the denervation-induced decrease of
preprotachykinin
messenger RNA when compared to animals injected with equivalent doses of nerve growth factor, neurotrophin-3, or vehicle. Neurotrophin-4/5 alone also normalized expression of messenger RNA encoding the 67 x 10(3) mol. wt isoform of glutamate decarboxylase, while none of the neurotrophins had a significant effect on preproenkephalin messenger RNA expression.(ABSTRACT TRUNCATED AT 250 WORDS)
...
PMID:Brain-derived neurotrophic factor and neurotrophin-4/5 modify neurotransmitter-related gene expression in the 6-hydroxydopamine-lesioned rat striatum. 761 69
Previous studies have demonstrated an antinociceptive effect of
brain-derived neurotrophic factor
(
BDNF
) following infusion into the midbrain, near the periaqueductal grey and dorsal raphe nuclei.
BDNF
administration attenuated the behavioural response in the tail-flick and hot-plate tests, two models employing a phasic, thermal high-intensity nociceptive stimulus; the present studies extend our previous findings to include a model of moderate, continuous pain resulting from a chemical stimulus, the formalin test. Midbrain infusion of
BDNF
decreased the behavioural paw flinch response to subcutaneous formalin injection in both the early and late phases of the test. As our previous studies showed that
BDNF
-induced analgesia was reversible by naloxone, we have examined the effects of
BDNF
administration on brain and spinal cord levels of neuropeptides involved in the modulation of nociceptive information, including the endogenous opioid peptides, met-enkephalin and beta-endorphin, as well as
substance P
and neuropeptide Y (NPY). At the site of infusion, within the PAG and dorsal raphe,
BDNF
increased the level of beta-endorphin by 63%, but had no effect on
substance P
, metenkephalin or NPY levels. In the dorsal spinal cord,
substance P
(113% increase), beta-endorphin (97% increase) and NPY (64% increase) were elevated, although ventral spinal cord levels of these peptides remained unchanged. These studies demonstrate a modulatory effect of
BDNF
on relevant neuropeptides within areas of the brain and spinal cord involved in the processing of nociceptive information.
...
PMID:BDNF produces analgesia in the formalin test and modifies neuropeptide levels in rat brain and spinal cord areas associated with nociception. 762 Jun 17
We have previously reported the isolation of an EGF-responsive precursor from the embryonic and adult mouse striatum. This precursor exhibits self renewal and the ability to produce a sphere of undifferentiated cells which can be induced to differentiate into neurons and glia. RT-PCR analysis of these spheres of undifferentiated cells revealed the expression of mRNA for the trkB neurotrophin receptor, both with and without the catalytic domain, and little or no expression of trkA or trkC. We examined the actions of
BDNF
on the fate of EGF-generated neural precursors. Ten days after a one-time exposure to
BDNF
, single EGF-generated spheres showed a twofold increase in neuron number and a marked enhancement in neurite outgrowth. Examination of neuronal nuclei with immunochemical probes for c-fos and bromodeoxyuridine revealed that the actions of
BDNF
were directly upon neuronal cells and did not involve division of neuronal precursors. The twofold increase in neuronal number due to
BDNF
, observed after 10 d in vitro, was significantly reduced after 21 d in vitro and was not apparent at 27 d in vitro. Quantitative analyses revealed that while repeated application of
BDNF
did not prevent the loss of neuron number over time, it did result in a significant increase in neurite numbers. Moreover, delayed addition of
BDNF
mimicked the increase in neuronal numbers seen when
BDNF
was present throughout. These
BDNF
actions did not appear to involve the enhancement of a novel neuronal phenotype, with all effects being due to increase in the numbers and neurite outgrowth of neurons that colocalize GABA and
substance P
. These findings suggest that
BDNF
markedly enhances the antigenic and morphologic differentiation of EGF-generated neuronal precursors.
BDNF
alone does not appear to act as a survival factor for neuronal precursors nor is it sufficient for preventing their death over time.
...
PMID:BDNF enhances the differentiation but not the survival of CNS stem cell-derived neuronal precursors. 764 17
The expression of neuropeptides and neurotrophic factors is altered in the hippocampus after seizure induction in rats. Because the increase in
brain-derived neurotrophic factor
(
BDNF
) and nerve growth factor (NGF) mRNAs precede changes in neuropeptide expression after seizure, it is possible that
BDNF
and NGF mediate subsequent alterations in peptide expression. To test this hypothesis directly,
BDNF
or NGF was infused into the hippocampus and cortex of adult rats. To ascertain the regional specificity of any observed effects of neurotrophin administration on neuropeptide expression, infusions into the striatum were also studied. To control for specificity, vehicle was also infused into the same sites. Peptide and mRNA alterations were assessed by Northern analysis, immunohistochemistry and radioimmunoassay.
BDNF
produced elevations of peptide and mRNA for neuropeptide Y and cholecystokinin in hippocampus and cortex, and somatostatin in cortex.
BDNF
increased mRNAs for neuropeptide Y, cholecystokinin,
substance P
and dynorphin in striatum. In contrast,
BDNF
decreased dynorphin peptide and mRNA in hippocampus. NGF's effects were limited to small mRNA increases, without corresponding changes in peptide levels, for neuropeptide Y in hippocampus and striatum,
substance P
in cortex and cholecystokinin in striatum. The distinct and limited effects of NGF infusion on neuropeptide expression demonstrate that
BDNF
's effects are not non-specific results of protein infusion into the brain. These findings indicate that
BDNF
may play a regionally specific role in modulating neuropeptide expression in the normal brain as well as in various pathophysiological states.
...
PMID:Regulation of neuropeptides in adult rat forebrain by the neurotrophins BDNF and NGF. 798 76
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