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)

The three-dimensional structure of physalaemin, pGlu-Ala-Asp-Pro-Asn-Lys-Phe-Tyr-Gly-Leu-Met-NH2, has been studied by one- and two-dimensional 500 MHz NMR spectroscopies in two solvents: methanol and dimethyl sulfoxide. As previously observed for substance P in methanol, the core of physalaemin 4----8 is folded into an helical conformation. This structure is stabilized by the presence of a salt bridge between Asp-3 and Lys-6 in both solvents. The only differences observed reside in the N-terminal sequences; the N-terminal tripeptide of substance is flexible whereas that of physalaemin is in an extended conformation.
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PMID:Conformational analogy between substance P and physalaemin. 242 2

Superfusion of slices from the dorsal half of the lumbar enlargement of rat spinal cord with Krebs-Henseleit medium supplemented with 30 microM bacitracin allowed the collection of substance P-like immunoreactive material (SPLI), which was released at a rate of approximately 10 pg/4 min. Tissue depolarization by an excess of K+ (30-60 mM) or veratridine (50 microM) induced a marked increase in SPLI outflow, provided that Ca2+ was present in the superfusing fluid. K+- or veratridine-induced SPLI overflow could be modulated in opposite directions by mu and delta opioid receptor agonists. Thus, the two preferential mu agonists Tyr-D-Ala-Gly-MePhe-Gly-ol (DAGO; 10 microM) and Tyr-D-Ala-Gly-MePhe-Met(O)5-OH (FK-33824; 0.1 microM) enhanced SPLI overflow from depolarized tissues, whereas the selective delta agonists Tyr-D-Thr-Gly-Phe-Leu-Thr (deltakephalin; 3 microM) and [2-D-penicillamine, 5-D-penicillamine]enkephalin (50 microM) reduced it. The effect of DAGO was antagonized by a low concentration (1 microM) of naloxone but not by the selective delta antagonist ICI-154129 (50 microM). In contrast, the latter drug prevented the inhibitory influence of delta agonists on K+-induced SPLI release. Complementary experiments with morphine (10 microM) and [2-D-alanine, 5-D-leucine]enkephalinamide (3 microM), in combination with 1 microM naloxone or 50 microM ICI-154129 for the selective blockade of mu or delta receptors, respectively, confirmed that the stimulation of mu receptors increased, whereas the stimulation of delta receptors reduced, SPLI overflow. The results suggest that, at the spinal level, and antinociceptive action of delta but not mu agonists might involve a presynaptic inhibition of substance P-containing primary afferent fibers.
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PMID:Opposite effects of delta and mu opioid receptor agonists on the in vitro release of substance P-like material from the rat spinal cord. 243 85

In the present paper the effects of substance P (SP1-11, Arg-Pro-Lys-Pro-Gln-Gln-Phe-Phe-Gly-Leu-MetNH2) and delta sleep inducing peptide (DSIP, Trp-Ala-Gly-Gly-Asp-Ala-Ser-Gly-Glu) to normalize the deprivation of sleep in chronically stressed rats with hyposomnia were investigated. The results indicated that SP1-11 is more potent than DSIP in rats with stress-induced hyposomnia. Different effects were found in the duration of sleep, the percentage of sleep phases compared to wake phases, the rhythm of sleep phases and the time periods of sleep-cycles. Based on the present results both the common and differences in the mode of action were discussed.
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PMID:[Comparison of the effects of DSIP and SP 1-11 on stress-induced chronic sleep disorders in rats]. 244 61

The effects of gamma-preprotachykinin-(72-92)-peptide amide [gamma-PPT-(72-92)-NH2] on salivation in the rat were investigated and were compared with salivation responses elicited by a variety of other tachykinin and related peptides. On intravenous injection or continuous infusion, gamma-PPT-(72-92)-NH2, a naturally occurring N-terminally extended derivative of neurokinin A (NKA), potently stimulated salivation. The rank order of potency of peptides that stimulated salivation was: NPK greater than gamma-PPT-(72-92)-NH2 greater than substance P greater than NKA = Asp-Ala-NKA. Moreover, gamma-PPT-(72-92)-NH2, like NPK, potentiated the effects of substance P on salivary secretion. These results indicate that the actions of gamma-PPT-(72-92)-NH2 may be pharmacologically or physiologically relevant in the actions of tachykinin peptides.
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PMID:gamma-Preprotachykinin-(72-92)-peptide amide potentiates substance P-induced salivation. 247 May 99

The neuropeptides neurotensin, substance P, neurokinin-alpha (substance K), and met-enkephalin are present endogenously in the ventral tegmental area (VTA), site of the A10 dopaminergic (DA) cell bodies. In the present study these four peptides were injected bilaterally into the VTA in the rat, and the effects on operant behavior were assessed. Cannulae aimed at the VTA were implanted in four groups of animals, which had been trained to bar-press for food reward on a fixed-interval, 40-s schedule. A fifth group, in which the effects of systemically administered amphetamine were assessed, was also tested. Response rate across the interval was measured, and the index of quarter-life was taken as an indication of the temporal pattern of responding. In addition, a rate-dependency analysis was carried out for all data. Neurotensin (NT, 0.0175, 0.175, 0.5 micrograms in 1 microliter) dose-dependently decreased response rates without affecting quarter-life, and reduced the number of reinforcements obtained. Substance P (SP, 0.1, 1.0, 3.0 micrograms) did not affect responding, and neurokinin-alpha (NKA, 0.1, 1.0, 3.0 micrograms) induced a small increase in responding. Quarter-life was not affected by SP or NKA, but responding on the non-reinforced lever was significantly increased by both peptides. d-Ala-met-enkephalin (DALA, 0.01, 0.1, 1.0 micrograms) induced a dose-dependent increase in responding which was also rate-dependent, and reduced quarter-life. DALA effects were similar to the classic pattern of responding observed after systemic amphetamine. These results suggest that although all these peptides elicit behavioral activation and may affect DA neuronal activity, the behavioral responses can be differentiated with respect to operant behavior.
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PMID:Neurotensin, substance P, neurokinin-alpha, and enkephalin: injection into ventral tegmental area in the rat produces differential effects on operant responding. 247 Dec 21

The common acute lymphoblastic leukemia antigen (CALLA) is a 749-amino acid type II integral membrane protein expressed by most acute lymphoblastic leukemias, certain other lymphoid malignancies with an immature phenotype, and normal lymphoid progenitors. A computer search against the most recent GenBank release (no. 56) indicates that human CALLA cDNA encodes a protein nearly identical to the rat and rabbit neutral endopeptidase 24.11 ("enkephalinase;" EC 3.4.24.11). This zinc metalloendopeptidase, which has been shown to inactivate a variety of peptide hormones including enkephalin, chemotactic peptide, substance P, neurotensin, oxytocin, bradykinin, and angiotensins I and II, had not been identified in lymphoid cells. To determine whether CALLA cDNA derived from human acute lymphoblastic leukemia cells (Nalm-6 cell line) encodes functional neutral endopeptidase activity, we generated CALLA+ stable transfectants in the CALLA- murine myeloma cell line J558 and analyzed them for enzymatic activity in a fluorometric assay based upon cleavage of the substrate glutaryl-Ala-Ala-Phe 4-methoxy-2-naphthylamide at the Ala-Phe bond. Total lysates as well as whole-cell suspensions of the Nalm-6 line and of the CALLA+ transfectants, but not of the CALLA- J558 cells, possessed neutral endopeptidase activity. This enzymatic activity was associated with the cellular membrane fraction and was abrogated by the specific neutral endopeptidase inhibitor phosphoramidon. The unequivocal identification of CALLA as a functional neutral endopeptidase provides insight into its potential role in both normal and malignant lymphoid function.
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PMID:Common acute lymphoblastic leukemia antigen (CALLA) is active neutral endopeptidase 24.11 ("enkephalinase"): direct evidence by cDNA transfection analysis. 252 88

A structure-activity study on neurokinin A and its C-terminal fragment NKA (4-10) has been performed in order to find selective agonists for the NK-2 receptor and identify chemical modifications suitable for protecting the peptides from degradation, while maintaining activity. Five series of compounds have been prepared and tested: 1. the complete series of the L-Ala monosubstituted analogues of NKA; 2. a series of NKA fragments from the C- or N-terminal; 3. the complete series of NKA (4-10) analogues monosubstituted with beta-Ala; 4. a series of NKA (4-10) analogues with monosubstitutions in pos. 4, 8, 10 or multisubstitutions in two or more of the same positions; and 5. a series of 6 NKA (4-10) analogues monosubstituted with 1-amino,1-cyclohexane carboxylic acid residue. It has been found that the most selective agonists for the NK-2 receptor system are [beta Ala8]NKA (4-10) and [Nle10]NKA (4-10). Protection from aminopeptidase may be obtained by acetylation of the N-terminal amide of NKA (4-10), while partial protection from endopeptidases should be expected from the presence of beta-Ala in position 8. Conformational constraints induced with 1,amino,1-cyclohexane carboxylic acid residue gave weakly active compounds. Multiple substitutions reduce rather than potentiating the favorable effects of the corresponding monosubstituted compounds.
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PMID:Structure-activity studies of neurokinin A. 254 91

The GRP receptor mediated growth response in Swiss 3T3 cells has been used to identify BN/GRP antagonists. Analysis of bombesin antagonism by substance P analogues and by truncated GRP analogues revealed that deletion of the C-terminal methionine residue was important for antagonism. Des-Met analogues showing potent antagonist activity in the in vitro 3T3 system (IC50 approximately 2nM) were synthesized. Further structural modification of these peptides led to the identification of (CH3)2CHCO-His-Trp-Ala-Val-D-Ala-His-Leu-NHCH3 (ICI 216140) which reduced bombesin-stimulated rat pancreatic amylase secretion to basal levels when administered subcutaneously at 2.0 mg per kg.
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PMID:N-isobutyryl-His-Trp-Ala-Val-D-Ala-His-Leu-NHMe (ICI 216140) a potent in vivo antaconist analogue of bombesin/gastrin releasing peptide (BN/GRP) derived from the C-terminal sequence lacking the final methionine residue. 255 38

From the soluble and membrane fractions of rat brain homogenate, two enzymes that liberate dipeptides of the type Xaa-Pro from chromogenic substrates were purified to homogeneity. The two isolated dipeptidyl peptidases had similar molecular and catalytic properties: For the native proteins, molecular weights of 110,000 were estimated; for the denatured proteins, the estimate was 52,500. Whereas the soluble peptidase yielded one band of pI 4.2 after analytical isoelectric focusing, two additional enzymatic active bands were detected between pI 4.2 and 4.3 for the membrane-associated form. As judged from identical patterns after neuraminidase treatment, both peptidases contained no sialic acid. A pH optimum of 5.5 was estimated for the hydrolysis of Gly-Pro- and Arg-Pro-nitroanilide. Substrates with alanine instead of proline in the penultimate position were hydrolyzed at comparable rates. Acidic amino acids in the ultimate N-terminal position of the substrates reduced the activities of the peptidases 100-fold as compared with corresponding substrates with unblocked neutral or, especially, basic termini. The action of the dipeptidyl peptidase on several peptides with N-terminal Xaa-Pro sequences was investigated. Tripeptides were rapidly hydrolyzed, but the activities considerably decreased with increasing chain length of the peptides. Although the tetrapeptide substance P 1-4 was still a good substrate, the activities detected for the sequential liberation of Xaa-Pro dipeptides from substance P itself or casomorphin were considerably lower. Longer peptides were not cleaved. The peptidases hydrolyzed Pro-Pro bonds, e.g., in bradykinin 1-3 or 1-5 fragments, but bradykinin itself was resistant. The enzymes were inhibited by serine protease inhibitors, like diisopropyl fluorophosphate or phenylmethylsulfonyl fluoride, and by high salt concentrations but not by the aminopeptidase inhibitors bacitracin and bestatin. Based on the molecular and catalytic properties, both enzymes can be classified as species of dipeptidyl peptidase II (EC 3.4.14.2) rather than IV (EC 3.4.14.5). However, some catalytic properties differentiate the brain enzyme from forms of dipeptidyl peptidase II of other sources.
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PMID:Purification of two dipeptidyl aminopeptidases II from rat brain and their action on proline-containing neuropeptides. 256 25

Neurons with intrinsic pacemaker activity and presumed sympathoexcitatory function were recorded in rat tissue slices within the confines of the rostroventrolateral reticular nucleus (RVL). These cells were excited in dose-dependent fashion by arginine vasopressin (AVP, 10(8)-10(6) M) but not by oxytocin (up to 10(7) M). The effect of AVP was mimicked by the V1-selective agonist [Phe2,Orn8]vasotocin (VT) (1 microM) but not by the V2-agonist [Val4,D-Arg8]vasopressin (VP) (1.9 microM). The effect of AVP (10(-7) M) was completely blocked by SKF 101926 (10(7) M), a non-selective antagonist and by d(CH2)5[Tyr(Me)2]AVP, a V1-selective antagonist but was unaffected by the V2-selective antagonist d(CH2)5[D-Ile2,Ile4,Ala-NH2 9]AVP. These cells were also activated by thyrotropin-releasing hormone (TRH) (10(-7)-10(-6) M), calcitonin gene-related peptide (CGRP) (4 X 10(-8) M), substance P, (10(-6) M), neuropeptide Y (NPY) (10(-8) M) and inhibited by Met-enkephalin (10(-6) M) and morphine (2 mM). Corticotropin-releasing factor (CRF) (10(-7) M) and angiotensin II (10(-6) M) were ineffective. In conclusion, RVL pacemaker neurons have vasopressin receptors reminiscent of the V1 (vascular and pressor) subtype. Their pacemaking activity is modulated by low doses of several other peptides also known to produce large vasomotor effects after introduction into the cerebroventricular space.
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PMID:Effects of vasopressin and other neuropeptides on rostral medullary sympathoexcitatory neurons 'in vitro'. 275


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