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)

Experimental herpes simplex keratitis in the mouse produced a rapid fall in both corneal sensitivity and levels of corneal substance P (SP). This finding supports the association of SP with sensory neurones and shows that such levels can be used as an indication of damage to neurones resulting, for example, from infection with HSV. However, the delay in recovery of SP compared to the more rapid and complete recovery of sensitivity suggests that SP in the cornea is not directly involved in mediation of the blink reflex.
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PMID:Corneal sensitivity and substance P in experimental herpes simplex keratitis in mice. 618 14

1. When dorsal root ganglia were incubated in vitro with a range of concentrations of anisomycin, incorporation of [ 3H ]lysine into protein and synthesis of substance P(SP) were inhibited to a similar extent confirming that SP is synthesised by a conventional ribosomal mechanism. 2. Doses of anisomycin sufficient to inhibit protein synthesis in mouse CNS in vivo by greater than 95% did not cause a significant fall in the SP content of any of five brain areas, spinal cord, dorsal root ganglia or cornea over an 8 h period. 3. Electrical stimulation of the hind limbs however, produced a 25% fall in the SP content of the dorsal spinal cord of these animals. 4. These findings suggest that the turnover-time of neuronal SP is much longer than that of non-peptide neurotransmitters.
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PMID:Effects of synthesis inhibition and nervous activity on concentrations of neuronal substance P. 619 31

Substance P (SP)-immunoreactive nerve fibres were searched for at all levels of both fetal and adult human lower respiratory tract. Because the demonstrability of substance P immunoreactivity varies between different animal species, rabbit pulmonary tissue was also subjected to SP immunohistochemistry. Human irises and corneas served as positive human controls. The specimens were taken from 10 human lungs during pulmonary operations. Tracheal tissue was obtained from three patients during bronchoscopy. Five fetal human lungs were examined. Human specimens examined included the trachea, main bronchi, segmental bronchi, and peripheral pulmonary tissue. In addition, the tracheobronchial tissues of four rabbits were studied. SP immunoreaction was demonstrated in formaldehyde-fixed cryostat sections by either the indirect immunofluorescence technique or the peroxidase-antiperoxidase procedure. Both monoclonal and conventional antibodies to SP were tested. In the rabbit SP-immunoreactive nerves were found in both the submucosa and the smooth muscle layer of the main bronchi and trachea. Specimens from human trachea, bronchi, and bronchioli were all negative. Since the SP immunoreaction was easily demonstrated in both human cornea and human iris, it was concluded that there are no SP-immunoreactive nerves in the human pulmonary tissues or that their SP content is very low and below the sensitivity of all the techniques used.
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PMID:Immunohistochemical demonstration of substance P in the lower respiratory tract of the rabbit and not of man. 619 99

The effects of capsaicin, the major pungent ingredient of hot peppers, were assessed on sensory neuron neuropeptide levels and on sensory function in the adult guinea pig. Systemic doses of capsaicin as low as 2.5 mg/kg depleted substance P (SP) in dorsal roots plus ganglia (DRG) whereas a 10-mg/kg dose depleted the peptide maximally in DRG and in the dorsal spinal cord. High doses of capsaicin had no consistent effects on levels of cholecystokinin (CCK), vasoactive intestinal polypeptide, or somatostatin, although a transient decrease in CCK levels was observed 4 days after dosing. A single 5-mg/kg dose of capsaicin rendered animals completely insensitive to chemical irritation of the cornea without affecting sensitivity to noxious heat. Higher doses of capsaicin produced a marked insensitivity to nociceptive and non-nociceptive heat as well as to chemical irritation without affecting other sensory modalities. The SP depletion and sensory deficits produced by a single 50-mg/kg dose of capsaicin were still evident 10 weeks later. The pattern of selectivity of the sensory deficits produced by capsaicin differed from that produced by morphine which was active against all forms of nociceptive stimuli. The results indicate that in the guinea pig capsaicin is potent at producing a unique, long-lasting syndrome of peripheral sensory deficits that may result from an effect of the agent on SP-containing primary afferent neurons.
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PMID:Characterization of the peptide and sensory neurotoxic effects of capsaicin in the guinea pig. 619 77

Some laboratories have obtained diverging results regarding the presence of substance P fibres in the cornea possibly because different antibodies were used. This has been further investigated by comparing results with several antibodies on identically treated sections from the anterior segment of rabbit eyes. In the uvea all antisera gave identical results showing substance P fibres in the iris and ciliary processes. In the cornea, on the other hand, polyclonal rabbit or guinea-pig antibodies gave high background fluorescence and no immunofluorescence fibres were detected. In contrast, the background staining was low with the monoclonal antibody so that substance p immunoreactive fibres could be demonstrated subepithelially, intraepithelially and in the corneal stroma.
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PMID:Substance P fibres in the anterior segment of the rabbit eye. 619 57

The overall distribution of substance P-like immunoreactive (SPI) fibers, examined by using whole-mounts of the rat cornea, was investigated by means of indirect immunofluorescence. SPI fibers entered the cornea from two levels; one from the middle layer of the sclera and the other from the episclera. From the sclera, a thick SPI fiber trunk, extending to the central part, subdivided into smaller SPI fiber bundles and approached the epithelium. The SPI fiber bundles from the episclera were smaller than those from the sclera. However, both fiber bundles formed a dense fiber network in the uppermost part of the stroma. This fiber plexus dissociated into SPI fibers extending to the superficial part of the epithelium where they formed an abundant arborization of fine SPI fibers. The results suggest that these fibers originate from SPI neurons in the trigeminal ganglion.
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PMID:Overall distribution of substance P nerves in the rat cornea and their three-dimensional profiles. 619 22

Nerves showing acetylcholinesterase (AChE) activity or immunoreactivity for substance P (SP) were demonstrated in the human cornea. AChE-positive fibres were found in stromal nerve trunks from where they penetrated Bowman's membrane and formed a basal epithelial plexus. Intraepithelial terminals arose from this network. SP immunoreactive nerve fibres showed similar architecture but were fewer. Both SP immunoreaction and histochemical AChE reaction were demonstrated consecutively in the same tissue section cut from both human and rabbit cornea. Stromal nerve trunks were found to contain SP immunoreactive and AChE-positive nerve fibres. However, the AChE-positive fibres were much more frequent than those immunoreactive for SP. In the rabbit Gasserian ganglion all neurons showed AChE activity but only some 20% were SP positive. It is concluded that all the sensory trigeminal nerve fibres of the cornea show AChE activity but only a proportion of them contain SP-like material.
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PMID:Substance P immunoreaction and acetylcholinesterase activity in the cornea and Gasserian ganglion. 619 9

The ontogeny of the substance P-like immunoreactivity (SPI) containing system in the ocular tissue of the rat was examined by means of the indirect immunofluorescence method. SPI-containing amacrine cells first appeared at postnatal day 4 and displaced SPI-containing amacrine cells at postnatal day 5. After this time, they developed markedly reaching their maximum content and distribution at postnatal day 14. On the other hand, SPI-containing cells in the trigeminal ganglion were first seen at gestational day 17 and reached their maximum content at birth. SPI-containing fibers in the cornea and uvea were first observed at gestational days 17-19. The SPI-containing fibers in the iris reached their maximum content at birth, while those in the cornea, choroid and ciliary body were fully developed at postnatal day 3. In the adult rats, numerous SPI structures were still seen in the ocular tissue, retina, cornea and uvea. These findings suggest that SPI might play some role in the developing ocular tissue in addition to its neurotransmitter or neuromodulator role in the adult, because SPI structures appear in the retina before establishment of synaptogenesis and in the cornea and uvea during the fetal stage.
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PMID:Ontogeny of substance P-containing structures in the ocular tissue of the rat: an immunohistochemical analysis. 620 77

Trigeminal ganglion cells supplying the cornea were traced with intra-axonally transported horseradish peroxidase and, subsequently studied for the presence of substance P-like immunoreactivity. Approximately 0%-30% of trigeminal ganglion cells contained immunoreactive substance P. These cells were of a small size (15-50 micrometers in diameter) and were distributed throughout the ganglion. The ganglion cells supplying the cornea were of a relatively small size as well but were confined to the anteromedial part of the ganglion. Some of these cells were found to contain immunoreactive substance P.
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PMID:Substance P-like immunoreactive trigeminal ganglion cells supplying the cornea. 620 64

Substance P (SP)-containing nerve fibers are few in the rabbit cornea, which is richly supplied with acetylcholinesterase-positive nerve fibers, presumably sensory in nature. Treatment with capsaicin given by retrobulbar injection 48 h prior to sacrifice caused SP to disappear from the SP nerves in the cornea without affecting the acetylcholinesterase-positive nerve fibers. The corneal sensitivity to a tactile stimulus (wetted cotton swabs) and to a chemical stimulus (local application of capsaicin) and the disruption of the blood-aqueous barrier after local injury (infrared irradiation of the iris) were tested after pretreatment with capsaicin (retrobulbar injection) the SP antagonist [D-Pro2,D-Trp7,9]SP (single topical application or long-term application twice daily for 2 months), the local anaesthetic oxibuprocaine (topical application), or the neuronal blocker tetrodotoxin (intravitreal injection). All these treatments abolished or reduced the disruption of the blood-aqueous barrier after local injury but only oxibuprocaine and tetrodotoxin abolished the corneal sensitivity to tactile and chemical stimuli. It is suggested that SP nerve fibers constitute a minor proportion of the sensory nerve supply to the cornea, that the neurogenic mechanisms involved in the response to ocular injury differ from those involved in corneal nociception, and that uveal SP is involved in the response to ocular trauma and that corneal SP is probably not necessary for corneal nociception.
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PMID:Is substance P necessary for corneal nociception? 620 85


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