Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P20366 (substance P)
 21,176 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

While the crucial role of neurally produced nitric oxide in mediating penile erection is well established, the understanding of the peripheral neuroanatomy of the nitric oxide-ergic pathways is still incomplete. This study was designed to elucidate further the distribution of nitric oxide synthase, and its relation to the distribution of neuropeptides and tyrosine hydroxylase in all penis-projecting neural pathways. A triple-labelling technique was employed, with the retrograde tracer Fluoro Gold combined with neuropeptide immunohistochemistry and nicotinamide adenine dinucleotide phosphate (NADPH)-diaphorase histochemistry, a marker of nitric oxide synthase. The presence within the penis of scattered nerve cell bodies exhibiting NADPH-diaphorase activity was revealed. Most (76%) of the penis-projecting neurons in the major pelvic ganglion exhibited NADPH-diaphorase activity and immunoreactivity to vasoactive intestinal peptide, while none of them contained tyrosine hydroxylase. Sympathetic paravertebral postganglionic neurons, in turn, contained tyrosine hydroxylase, but did not exhibit NADPH-diaphorase activity. In the afferent, sensory neurons projecting to the penis from the dorsal root ganglia, NADPH-diaphorase activity coexisted with immunoreactivity to both substance P (8%) and calcitonin gene-related peptide (26%). Preganglionic neurons originating in the spinal cord intermediolateral column at the thoracolumbar level T11-L3 terminated, not only in the major pelvic ganglion, but also within the penis. The majority (81%) of the penis-projecting neurons exhibited NADPH-diaphorase activity. The results indicate that the rat penis receives several different nitric oxide-ergic neural projections. It is therefore possible that nitric oxide affects penile erection at several neuronal levels.
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PMID:Nitric oxide-synthesizing neurons originating at several different levels innervate rat penis. 895 82

While systemic capsaicin in adult rats is known to reduce substance P and somatostatin in primary sensory nerves, it is still unknown if it also affects the production of these peptides at the genetic level. Therefore, we examined the effects of systemically administered capsaicin on the expression of the beta-preprotachykinin, gamma-preprotachykinin, somatostatin, calcitonin gene-related peptide, vasoactive intestinal polypeptide, galanin, neuropeptide Y and neurotrophin receptor family (trkA, trkB, trkC) genes in dorsal root ganglion neurons by in situ hybridization in adult rats. Nerve growth factor is thought to be involved in the regulation of some of these genes. In the control animals, beta-preprotachykinin, gamma-preprotachykinin, calcitonin gene-related peptide, somatostatin, trkA, trkB and trkC messenger RNAs were found in about 30%, 30%, 40%, 10%, 40%, 5% and 20% of the lumbar dorsal root ganglion neurons, respectively. The number of neurons expressing beta/gamma-preprotachykinin and calcitonin gene-related peptide messenger RNAs decreased to about 50% and 70% of the control values, respectively, six days after subcutaneous administration of capsaicin (950 mg/kg). Simultaneously, the number of trkA messenger RNA-expressing neurons also decreased to about 70% of the control level, while the number of neurons expressing trkB and trkC messenger RNAs was unaffected. On the other hand, vasoactive intestinal polypeptide and galanin messenger RNAs, but not neuropeptide Y messenger RNA, began to be expressed in about 10% of dorsal root ganglion neurons after administration of capsaicin, although their messenger RNAs were not detected in the controls. However, the expression of somatostatin messenger RNA was unaffected by the systemic administration of capsaicin. The somatostatin messenger RNA was not co-expressed with vasoactive intestinal polypeptide and galanin messenger RNAs in the sensory neurons of rats given capsaicin. Electron microscopic analysis revealed a few degenerating unmyelinated afferents in sural nerves of the treated rats. The number of small-sized dorsal root ganglion cells labeled with Fluoro-Gold, a retrograde-tracing dye which was injected into the sural nerve of the treated rats, decreased to half of the control number. Our results suggest that systemic administration of capsaicin in adult rats depresses the expression of beta/gamma-preprotachykinin, calcitonin gene-related peptide and trkA messenger RNAs, and induces expression of vasoactive intestinal polypeptide and galanin messenger RNAs in sensory neurons, which may be due to the capsaicin-induced degeneration of a subpopulation of sensory afferents. We also demonstrated that the regulation of somatostatin gene expression in mature sensory neurons is not affected by systemic capsaicin.
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PMID:Systemic capsaicin in the adult rat differentially affects gene expression for neuropeptides and neurotrophin receptors in primary sensory neurons. 897 80

Primary afferent neurons containing substance P (SP) are apparently implicated in the transmission of noxious information from the periphery to the central nervous system, and SP released from primary afferent neurons acts on second-order neurons with the SP receptor (SPR). In the rat, nociceptive information reached the hypothalamus not only through indirect pathways but also directly through trigeminohypothalamic and spinohypothalamic pathways. Thus, in the present study, the distribution pattern of trigeminohypothalamic and spinohypothalamic tract neurons showing SPR-like immunoreactivity (SPR-LI) was examined in the rat by a retrograde tract-tracing method combined with immunofluorescence histochemistry for SPR. A substantial number of trigeminal and spinal neurons with SPR-LI were retrogradely labeled with Fluoro-Gold (FG) injected into the hypothalamic regions. These neurons were distributed mainly in lamina I of the medullary and spinal dorsal horns, lateral spinal nucleus, regions around the central canal of the spinal cord, and the lateral aspect of the deep part of the spinal dorsal horn. A number of SPR-LI neurons in the spinal parasympathetic nucleus were labeled with FG injected into the area around the paraventricular hypothalamic nucleus. Some SPR-LI neurons in the lateral spinal nucleus and the lateral aspect of the deep part of the spinal dorsal horn were also labeled with FG injected into the septal region. On the basis of the distribution areas of SPR-LI trigeminal and spinal neurons projecting to the hypothalamic and septal regions, it is likely that these neurons are involved in the transmission of somatic and/or visceral noxious information.
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PMID:Distribution of trigeminohypothalamic and spinohypothalamic tract neurons displaying substance P receptor-like immunoreactivity in the rat. 903 7

The anterograde neuronal tracing properties of Fluoro-Gold (FG) were characterized in this study by its ability to label the retinohypothalamic tract (RHT) upon pressure injection of the substance into the vitrous body of the eye in the Djungarian hamster, Phodopus sungorus. Tracing was compared to the anterograde neuronal transport of cholera toxin B subunit (CTB), Fast blue (FB), Phaseolous vulgaris leucoagglutinin (PHA-L) and biocytin. After survival times that ranged from 24 h to 4 weeks, a major projection was found to the bilateral hypothalamic suprachiasmatic nuclei (SCN). Labeling was also found in the anterior medial preoptic nucleus and, in relatively sparse amounts, in the lateral geniculate nucleus, superior colliculus and lateral habenular nucleus. Similar results were obtained upon injection of CTB or FB, respectively, into the eye, whereas the application of PHA-L or biocytin did not label retinal afferents. The combined injection of FG and CTB or FB into the same eye labeled retino-afferent fibers only when FG was applied three days before the injection of the other tracers. Retrogradely labelled neurons were sen occasionally in the hypothalamus which may provide a sparse retinopetal projection. Additional experiments combining FG tracing and the immunofluorescent detection of the neuropeptides substance P (SP) or vasoactive intestinal polypeptide (VIP) in the SCN showed that FG-containing punctae were accumulated in the vicinity of immunoreactive cell bodies. Our data demonstrate that FG may be used as an anterograde axonal tracer of the retinohypothalamic pathway.
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PMID:Anterograde tracing of retinohypothalamic afferents with Fluoro-Gold. 903 10

Retrograde tracing with Fluoro-Gold was used to identify the complete population of knee joint afferents in the lumbar dorsal root ganglia of adult female Wistar rats. There was an average of 581 +/- 31 (mean +/- S.D.) afferents supplying each joint. These were found distributed from L1 to L5 with the great majority localised in the L3 and L4 ganglia. Electron microscopy of the posterior articular nerve of the knee revealed an average of 103 +/- 15 (mean +/- S.D.) myelinated and 513 +/- 39 unmyelinated axonal profiles. Since about 50-60% of the unmyelinated profiles would be expected to be sympathetic efferents, these numbers are consistent with the numbers of afferents found by Fluoro-Gold retrograde tracing and suggest that the posterior articular nerve contains about 50% of the total number of knee joint afferents in the rat. Immunohistochemistry revealed that an average of 10% of identified joint afferents expressed substance P-like immunoreactivity and that 33% expressed calcitonin gene-related peptide-like immunoreactivity.
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PMID:Number, distribution and neuropeptide content of rat knee joint afferents. 918 75

Substance P receptor (SPR)-immunoreactive neurons projecting to the periaqueductal gray (PAG) were examined in the rat spinal trigeminal nucleus and spinal cord by a retrograde tracing method combined with immunofluorescence histochemistry. After injection of Fluoro-gold (FG) into the PAG, SPR-immunoreactive neurons labeled with FG were observed mainly in the lateral spinal nucleus and lamina I of the medullary and spinal dorsal horns and additionally in laminae V and X of the spinal cord.
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PMID:Substance P receptor (NK1)-immunoreactive neurons projecting to the periaqueductal gray: distribution in the spinal trigeminal nucleus and the spinal cord of the rat. 959 32

The nucleus accumbens (NAcc) can be subdivided into 'core' and 'shell' based on anatomical connections and histochemical markers. Previous studies have demonstrated dopamine-beta-hydroxylase immunoreactive (DBH-ir) fibers in the NAcc shell, but the source of these noradrenergic (NE) afferents has not been determined. Therefore, we have investigated in detail the anatomy of NE afferents to this subregion. Dual immunohistochemistry for DBH and substance P demonstrated numerous DBH-ir fibers in the caudal NAcc shell. Neurons projecting to the NAcc were identified with Fluoro-Gold (FG) or cholera toxin B (CTb) retrograde tracing and tyrosine hydroxylase (TH) immunohistochemistry. Single- and double-labeled neurons were observed in the A2 and A1 NE cell groups following FG injections into the caudal NAcc shell. Numerous FG and CTb single-labeled neurons were found in the rostral locus coeruleus (LC), subcoeruleus and pericoerulear dendritic region, with an occasional double-labeled neuron in the LC. Few labeled neurons were seen in the brainstem after FG injections into the NAcc core, consistent with the lack of DBH-ir in this subterritory. To confirm these results, injections of Phaseolus vulgaris leucoagglutinin or biotinylated dextran amine were made into the LC or nucleus tractus solitarius (NTS). Virtually no labeled fibers were observed in the NAcc following injections into central LC. However, fibers were observed in the NAcc shell after injections in the NTS. These results indicate that the primary source(s) of NE afferents to the NAcc shell is the A2 region of the NTS, with lesser contributions from A1 and LC.
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PMID:Origin of noradrenergic afferents to the shell subregion of the nucleus accumbens: anterograde and retrograde tract-tracing studies in the rat. 973 25

The present study was conducted to investigate the distribution and immunohistochemical characteristics of ascending and descending projection neurons of the rat superior olivary complex (SOC), a group of interrelated brainstem nuclei. Ascending neurons were identified by injection of cholera toxin B subunit (CTB) into the central nucleus of the inferior colliculus (IC), descending neurons were labeled by application of Fluoro-Gold (FG) into the scala tympani of the cochlea, ipsilaterally to the IC injection. In accordance with the literature, we observed neurons innervating the IC located in the lateral superior olivary nucleus (LSO) and dorsal periolivary groups (DPO) on both sides, in the superior paraolivary nucleus (SPO) predominantly ipsilateral, as well as in the ipsilateral medial superior olivary nucleus (MSO) and the medial nucleus of the trapezoid body (MNTB). Cochlear projection neurons were found predominantly in the ipsilateral LSO as well as in the bilateral SPO, DPO, MSO and MNTB. In addition, a considerable population of neurons in the ipsilateral LSO and SPO were identified as being both ascending and descending. To further characterize these double-projecting neurons, brainstem sections were incubated in antisera directed against different neuroactive substances. The majority of ascending/descending cells in the LSO contained calcitonin gene-related peptide, but not substance P (SP), met-enkephalin (ENK) or tyrosine hydroxylase (TH). Some of these neurons apparently were contacted by ENK- or SP-immunoreactive fibers and terminals. In addition, we found TH-immunoreactive neurons in the lateral MNTB region. These neurons, which were labeled upon tracer injection into the cochlea (but not upon IC injection), probably belong to the C1 catecholaminergic cell group and may represent a division of the uncrossed olivocochlear bundle. The present results reveal the existence of a previously unknown subpopulation of SOC neurons that project to both the cochlea and the inferior colliculus. Their CGRP immunoreactivity and their uncrossed projection pattern provide evidence that they may belong to the cholinergic, putatively excitatory cell group.
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PMID:Immunfluorescence study of neuropeptides in identified neurons of the rat auditory superior olivary complex. 1039 79

We sought to determine whether pontomesencephalic cholinergic neurons which we have been shown previously to project to the substantia nigra and ventral tegmental area also contribute to the thalamic activation projection from the pedunculopontine and laterodorsal tegmental nuclei. Retrograde tracing, immunohistochemical localization of choline acetyltransferase and statistical methods were used to determine the full extent of the cholinergic projection from the pedunculopontine and laterodorsal tegmental nuclei to the thalamus. Progressively larger Fluoro-Gold injections in to the thalamus proportionally labeled increasing numbers of pontomesencephalic cholinergic cells both ipsi- and contralaterally in the pedunculopontine and laterodorsal tegmental nuclei. Multiple large thalamic injections left only a small fraction of the ipsilateral pontomesencephalic cholinergic group unlabeled. This small remainder did not correspond to the populations which project to the substantia nigra and ventral tegmental area, thereby indicating that substantia nigra- and ventral tegmental area-projecting cholinergic neurons must also project to the thalamus. We examined whether there existed any set of cholinergic neurons in the pedunculopontine and laterodorsal tegmental nuclei which did not innervate a thalamic target. The distribution of descending projections of the pedunculopontine and laterodorsal tegmental nuclei demonstrated that the unlabeled remainder cannot correspond to a purely descending group. We also show that substance P-positive cholinergic cells in the laterodorsal tegmental nucleus project to the thalamus. Further studies demonstrated that the small population of cholinergic cells left unlabeled from the thalamus were the smallest sized cholinergic cells, and included two groups of small, light-staining cholinergic cells located in the parabrachial area and central gray, adjacent to the main pedunculopontine and laterodorsal tegmental nuclei cholinergic groups. These small cells, in contrast to thalamic-projecting cholinergic cells, did not stain positively for reduced nicotinamide adenine dinucleotide phosphate-diaphorase. Taken together, these results indicated that all of the reduced nicotinamide adenine dinucleotide phosphate diaphorase-positive/choline acetyltransferase-positive neurons of the pedunculopontine/laterodorsal tegmental nuclei ascend to innervate some portion of the thalamus, in addition to the other targets they innervate. These findings indicate that the diverse physiological and behavioral effects attributed to the activity of pontomesencephalic cholinergic neurons should not be dissociated from their activating effects in the thalamus.
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PMID:Characterization of the extent of pontomesencephalic cholinergic neurons' projections to the thalamus: comparison with projections to midbrain dopaminergic groups. 1057 14

Neurons of the mesencephalic trigeminal nucleus (MTN) are considered to be homologous to mechanosensitive neurons in the sensory ganglia. The sites of origin of serotonin (5HT)-immunoreactive axons on neuronal cell bodies in the MTN were studied in the rat by combining immunofluorescence histochemical techniques with retrograde tracing of Fluoro-Gold (FG) and anterograde tracing of biotin-conjugated dextran amine (BDA). The tracing studies, which were combined with multiple-labeling immunohistochemistry and confocal microscopy, indicated that 5HT-immunoreactive axon terminals on the cell bodies of MTN neurons originated from the medullary raphe nuclei, such as the nucleus raphes magmus (RMg), alpha part of the nucleus reticularis gigantocellularis (GiA) and nucleus raphes obscurus (ROb), as well as from the mesopontine raphe nuclei, such as the nucleus raphes dorsalis (DR), nucleus raphes pontis (PnR) and nucleus raphes medianus (MnR); mainly from the RMg, GiA and DR, and additionally from the ROb, PnR and MnR. The cell bodies in close apposition to 5HT-immunoreactive axon terminals were found through the whole rostrocaudal extent of the MTN. Electron microscopically a number of axon terminals that were labeled with BDA injected into the raphe nuclei were confirmed to be in asymmetric synaptic contact with the cell bodies of MTN neurons. It was also indicated that substance P existed in some of the 5HT-containing axosomatic terminals arising from the ROb, RMg and GiA. The present results indicated that proprioceptive sensory signals from the muscle spindles or periodontal ligament might be modulated at the level of the primary afferent cell bodies in the MTN by 5HT-containing axons from the mesopontine and medullary raphe nuclei including the GiA.
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PMID:Serotonergic innervation of mesencephalic trigeminal nucleus neurons: a light and electron microscopic study in the rat. 1086 75


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