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Regoli D, Drapeau G, Dion S, D'Orléans-Juste P. Pharmacological receptors for substance P and neurokinins. Life Sci 1987; 40:109-17. [PMID: 2432376 DOI: 10.1016/0024-3205(87)90349-3] [Citation(s) in RCA: 286] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The three neurokinins identified in mammals, substance P, neurokinin A and neurokinin B, as well as their C-terminal biologically active fragments, have been used to characterize the responses of a variety of isolated organs. Three preparations selective either for substance P (the dog carotid artery), or for neurokinin A (the rabbit pulmonary artery) or for neurokinin B (the rat portal vein) are described. A neurokinin receptor classification is attempted using the neurokinins and their fragments to determine the order of potency of agonists. Three receptor subtypes have been identified: the NK-P, on which substance P (SP) is more active than neurokinin A (NKA) and neurokinin B (NKB), and the neurokinins are more active than their respective fragments; the NK-A on which NKA greater than NKB greater than SP, and some NKA fragments are more discriminative than their precursor; the NK-B on which NKB greater than NKA greater than SP, and fragments of NKB are less active than their precursor. Among the peptides studied, some potent compounds have been identified that could provide selective receptor ligands.
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Abstract
Endothelins are produced by endothelial and epithelial cells, macrophages, fibroblasts, and many other types of cells. Their receptors are present in numerous cells, including smooth muscle cells, myocytes, and fibroblasts. Evidence now suggests that the three isoforms of endothelins (ET-1 and the other two related isopeptides, ET-2 and ET-3) regulate growth in several of these cells. Endothelin-1 influences DNA synthesis, the expression of protooncogenes, cell proliferation, and hypertrophy. The participation of ET in mitogenesis involves activation of multiple transduction pathways, such as the production of second messengers, the release of intracellular pools of calcium, and influx of extracellular calcium. Moreover, ET-1 acts in synergism with various factors, such as EGF, PDGF, bFGF, TGFs, insulin, etc., to potentiate cellular transformation or replication. Several of these factors may in turn stimulate the synthesis and/or the release of endothelins. The production and release of endothelins are also increased in acute and chronic pathological processes, e.g., atherosclerosis, postangioplastic restenosis, hypertension, and carcinogenesis. It is postulated that endothelins act in a paracrine/autocrine manner in growth regulation and play an important role mediating vascular remodeling in some cardiovascular diseases. The present review analyses the implication of endothelins (ET-1, -2, and -3) in physiopathology related to their growth regulatory properties.
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Drapeau G, D'Orléans-Juste P, Dion S, Rhaleb NE, Rouissi NE, Regoli D. Selective agonists for substance P and neurokinin receptors. Neuropeptides 1987; 10:43-54. [PMID: 2444902 DOI: 10.1016/0143-4179(87)90088-6] [Citation(s) in RCA: 211] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
A series of neurokinin analogues and fragments have been prepared in an attempt to identify selective agonists for NK-P, NK-A and NK-B receptors. The compounds have been tested on the dog carotid artery (NK-P receptor system), the rabbit pulmonary artery (NK-A) and the rat portal vein (NK-B). C-terminal substituted analogues of the three neurokinins have provided indication that NK-P receptor selectivity is improved by the oxidation of methionine to Met(O2), while selectivity for NK-A is favoured by replacing Met with NIe. Selectivity for NK-P receptors is further improved by the replacement of Gly9 with Sar. Selectivity and affinity for NK-B receptors is markedly increased when Val7 is replaced with MePhe in both the fragment NKB (4-10) and NKB. The results of the present study indicate that a) [Sar9,Met(O2)11]SP is a potent and selective agonist for the NK-P receptors of the dog carotid artery; b) [MePhe7]NKB is a very potent and selective stimulant of receptors for neurokinin B and c) [Nle10]NKA (4-10) is a promising compound, showing some selectivity for NK-A receptor; further modifications are however needed to improve its affinity.
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D'Orléans-Juste P, Dion S, Mizrahi J, Regoli D. Effects of peptides and non-peptides on isolated arterial smooth muscles: role of endothelium. Eur J Pharmacol 1985; 114:9-21. [PMID: 3930267 DOI: 10.1016/0014-2999(85)90515-1] [Citation(s) in RCA: 152] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Peptides and non-peptides acting as vasoconstrictors or vasodilators have been tested in dog isolated carotid arteries with and without endothelium and in the presence and absence of a variety of antagonists and inhibitors of endogenous substances. It has been found that substance P and several other tachykinins, bradykinin, neurotensin, bombesin and acetylcholine relax the isolated artery only when the endothelium is present, while VIP, isopropylnoradrenaline, adenosine, histamine, prostaglandins E1 and E2, glucagon and insulin relax and angiotensin, vasopressin, oxytocin, 5-HT and noradrenaline contract the isolated vessel, no matter whether the endothelium is present or not. Peptide and non-peptide antagonists have been used with success to show that vasoconstrictors and vasodilators act on specific receptors, since their effects are reduced in the presence of antagonists, specific for one or another of the various agents. Inhibitors of the arachidonic acid cascade only reduce the effect of acetylcholine, suggesting that at least two different mechanisms are involved in the endothelium-mediated relaxation of arterial smooth muscles to peptide and non-peptide agents. The results summarised in this paper suggest that the site of action of several vasodilators is the endothelium, while other vasodilators and all the vasoconstrictors influence the arterial vessels tone presumably by acting on the smooth muscle cells.
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Regoli D, Drapeau G, Dion S, D'Orléans-Juste P. Receptors for substance P and related neurokinins. Pharmacology 1989; 38:1-15. [PMID: 2542998 DOI: 10.1159/000138512] [Citation(s) in RCA: 150] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The most widely used smooth muscle preparations for neurokinin bioassays have been critically analyzed in order to determine whether neurokinins act directly or by the intermediary of other natural agents. Indeed, part of the contraction of the GPI in response to neurokinins appears to be mediated by acetylcholine and possibly prostaglandins. Active metabolites of the arachidonic acid cascade also intervene in the response of the HUB. Neurokinins produce relaxation of the DCA by stimulating the release of a vascular smooth muscle relaxing factor from the endothelium. In the other preparations (the RD, the RPA without endothelium and the RPV) neurokinins may act directly on the smooth muscle fibers. Neurokinins produce their biological effects by activating specific receptors. Three different receptor types, one for each mammalian neurokinin, have been identified by using four groups of natural peptide sequences and some selective agonists. The receptor for SP is particularly sensitive to SP and physalaemin and shows higher affinity for the whole natural peptides (SP, NKA) than for their C-terminal fragments. The receptor for neurokinin A is highly sensitive to NKA and eledoisin: it shows high affinity for heptapeptide fragments such as NKA4-10 and SP5-11. The receptor for NKB is sensitive to NKB and kassinin more than to the other natural peptides and their fragments. The natural peptides show however little selectivity. Synthetic analogues active on a single receptor type (selective agonists) have been used to find out whether the responses of the isolated organs are due to the activation of one or more than one receptor. It has been found that the GPI, the RD and the HUB contain all three or at least two receptors, while the DCA has only the NK1, the RPA has only the NK2 and the RPV only the NK3 type. Binding sites specific for each neurokinin have been identified in brain and peripheral organs with accurate biochemical assays, using labeled neurokinins. Competitive displacement assays have been performed with a variety of neurokinin-related peptides, and their Ki have been determined. By plotting Ki values against the ED50, estimated from biological assays, positive significant correlations have been found for the monoreceptor (DCA, RPA, RPV) but not for the multiple receptor systems (GPI, RD, HUB). This suggests that pharmacological receptors may be identical with the recognition sites which bind the labeled neurokinins. The availability of monoreceptor systems and of selective agonists opens the way for the identification of potential antagonists and accurate estimation of their affinities.(ABSTRACT TRUNCATED AT 250 WORDS)
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Dion S, D'Orléans-Juste P, Drapeau G, Rhaleb NE, Rouissi N, Tousignant C, Regoli D. Characterization of neurokinin receptors in various isolated organs by the use of selective agonists. Life Sci 1987; 41:2269-78. [PMID: 2824947 DOI: 10.1016/0024-3205(87)90538-8] [Citation(s) in RCA: 134] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The three mammalian neurokinins, substance P, neurokinin A and neurokinin B, as well as some agonists selective for their respective receptors, NK-P, NK-A and NK-B, were tested in a variety of pharmacological preparations in order to evaluate if the biological responses of the various tissues were mediated by single or multiple receptor types. Previous observations that the dog carotid artery, the rabbit pulmonary artery and the rat portal vein are selective preparations respectively for SP, NKA and NKB were confirmed in the present study by showing that only the respective selective agonists were active on these tissues. Multiple functional sites were demonstrated in intestinal tissues (guinea pig ileum, rat duodenum), which apparently contain the three neurokinin receptors. A large number of NK-P, together with some NK-A receptor sites were found in the guinea pig and rat urinary bladder. Similarly, the guinea pig trachea and the rabbit mesenteric vein contain NK-A and NK-P functional sites. Rat and rabbit vas deferens stimulated electrically respond as typical NK-A preparations, since they are almost insensitive to SP or NKB selective agonists. A mixture of NK-A and NK-B receptor sites has been shown to be present in the hamster urinary bladder: dog and human urinary bladder definitely contain NK-A receptors and the dog bladder also some NK-P functional sites.
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D'Orléans-Juste P, Dion S, Drapeau G, Regoli D. Different receptors are involved in the endothelium-mediated relaxation and the smooth muscle contraction of the rabbit pulmonary artery in response to substance P and related neurokinins. Eur J Pharmacol 1986; 125:37-44. [PMID: 2426129 DOI: 10.1016/0014-2999(86)90081-6] [Citation(s) in RCA: 122] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Four neurokinins, substance P (SP), neurokinin A (NKA) neurokinin B (NKB) and kassinin (Kass) were used in the present study together with other peptides and nonpeptide agents to demonstrate the existence of two different neurokinin receptor types in the rabbit isolated pulmonary artery. Similar to other arterial vessels, the endothelium-dependent relaxation of the pulmonary artery in response to neurokinins is due to the activation of a SP-P receptor more sensitive to SP than to the other neurokinins. The endothelium-dependent relaxation is an indirect phenomenon, mediated by an unknown endothelial agent, similar to that released by acetylcholine. The contraction of the pulmonary artery in response to neurokinins is due to receptors of the NK-A type, particularly sensitive to NKA and NKB, and much less sensitive to SP. The contraction is a direct phenomenon, apparently not involving any of the known endogenous autacoids and neurotransmitters or metabolites of arachidonic acid. Contraction appears to be due to stimulation by the neurokinins of receptors located in the arterial smooth muscle. The results presented in this paper indicate that NK-A receptors for neurokinins (which are present in the tracheo-bronchial tree) are also to be found in pulmonary vessels and mediate contraction of arterial vascular smooth muscle, an interesting property of neurokinins.
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Mastrangelo D, Mathison R, Huggel HJ, Dion S, D'Orléans-Juste P, Rhaleb NE, Drapeau G, Rovero P, Regoli D. The rat isolated portal vein: a preparation sensitive to neurokinins, particularly neurokinin B. Eur J Pharmacol 1987; 134:321-6. [PMID: 3471518 DOI: 10.1016/0014-2999(87)90363-3] [Citation(s) in RCA: 118] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
The rat isolated portal vein is a pharmacological preparation more sensitive to neurokinin B than to any other neurokinin or tachykinin. The preparation is more sensitive to C-terminal partial sequences of substance P (SP) particularly SP-(6-11) than to the whole undecapeptide. The order of potency of neurokinins is as follows: neurokinin B greater than neurokinin A greater than substance P. The preparation shows high sensitivity also to kassinin and eledoisin. Comparative tests performed with strips of the rat portal vein suspended in a microbath under continuous perfusion (system 1) or in ordinary baths for isolated smooth muscles (system 2) have given similar results and have shown that the myotropic effect of neurokinin B is not modified by a variety of antagonists of endogenous agents as well as by inhibitors of the arachidonic acid cascade. The present results suggest that neurokinin B contracts the rat portal vein by activating specific receptors, presumably located on the smooth muscle membrane, different from those of biologically active amines and peptides which are active stimulants of the vein. Neurokinin B is ten times more active than neurokinin A and at least 100 times more than substance P. Such an order of potency of agonists suggests the existence of a new neurokinin receptor type, particularly sensitive to neurokinin B.
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D'Orléans-Juste P, Labonté J, Bkaily G, Choufani S, Plante M, Honoré JC. Function of the endothelinB receptor in cardiovascular physiology and pathophysiology. Pharmacol Ther 2002; 95:221-38. [PMID: 12243796 DOI: 10.1016/s0163-7258(02)00235-8] [Citation(s) in RCA: 115] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
One of the two receptors by which the potent vasoactive effects of endothelin (ET)-1 are mediated is the ET(B) receptor (ET(BR)), which is found in several tissues, but, more importantly from a cardiovascular point of view, on the endothelial cell. The endothelial cell also has the unique capability of releasing ET-1, as well as other factors, such as the endothelial-derived relaxing factors and prostacyclin, which counteract the myotropic effects of the peptide. The secretory and contractile responses to ET-1 rely on G-protein-coupled ET(BR)s, as well as ET(A)-G-protein-coupled receptor-like proteins. The mitogenic properties of ET-1 via ET(A) receptors (ET(AR)s) coupled to mitogen-activated protein kinases and tyrosine kinases on the vascular smooth muscle may occur in conjunction with the anti-apoptotic characteristics of the endothelial ET(BR)s. Interestingly, most of the relevant antagonists and agonists for both ET(AR)s and ET(BR)s have been developed by the pharmaceutical industry. This highlights the therapeutical potential of compounds that act on ET receptors. In normal as well as in physiopathological conditions, the ET(BR) plays an important role in the control of vascular tone, and must be taken into account when using ET receptor antagonists for the treatment of cardiovascular diseases. For the management of congestive heart failure, renal failure and primary pulmonary hypertension, the most recent literature supports the use of selective ET(AR) antagonists rather than mixed antagonists of ET(AR)s and ET(BR)s. Nonetheless, validation of this view will have to await the first clinical trials comparing the actions of ET(A) to mixed ET(A)/ET(B) receptor antagonists.
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D'Orléans-Juste P, de Nucci G, Vane JR. Kinins act on B1 or B2 receptors to release conjointly endothelium-derived relaxing factor and prostacyclin from bovine aortic endothelial cells. Br J Pharmacol 1989; 96:920-6. [PMID: 2545298 PMCID: PMC1854440 DOI: 10.1111/j.1476-5381.1989.tb11903.x] [Citation(s) in RCA: 89] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
1. Bradykinin (Bk) induced the coupled release of endothelium-derived relaxing factor (EDRF) and prostacyclin (PGI2) from bovine aortic endothelial cells grown in culture. The B2 kinin receptor antagonist, [D-Arg0,Hyp3,Thi5,8,D-Phe7]-Bk, abolished this release by Bk. 2. Des-Arg9-Bk, a B1 kinin receptor agonist, also induced the release of EDRF and PGI2, but much higher concentrations were required to obtain a similar release to that induced by Bk. 3. [Leu8],des-Arg9-Bk, a B1 receptor antagonist, significantly reduced the response to des-Arg9-Bk without affecting the release induced by Bk. 4. The release of EDRF and PGI2 induced by arachidonic acid or ADP was not significantly affected by the B2 or the B1 antagonist. 5. We conclude, therefore, that Bk and des-Arg9-Bk were acting respectively on B2 and B1 bradykinin receptors. 6. The possible role of kinin receptors in the release of EDRF and PGI2 from endothelial cells is discussed.
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Regoli D, Drapeau G, Rovero P, Dion S, D'Orléans-Juste P, Barabé J. The actions of kinin antagonists on B1 and B2 receptor systems. Eur J Pharmacol 1986; 123:61-5. [PMID: 2872074 DOI: 10.1016/0014-2999(86)90687-4] [Citation(s) in RCA: 81] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The newly discovered bradykinin antagonist [Thi5,8,D-Phe7]Bradykinin, supplied by J.-M. Stewart and three other compounds, [D-Phe7]BK, [Thi5,8,D-Phe7]Bradykinin and [Thi6,9,D-Phe8]Kallidin synthesized in our laboratory, were tested for their ability to antagonize bradykinin in four B2 receptor systems, the guinea-pig ileum, the rabbit jugular vein, the dog carotid artery and the dog urinary bladder as well as against desArg9-bradykinin in the rabbit aorta (a B1 receptor system). [D-Phe7]Bradykinin is a partial agonist, while [Thi5,8,D-Phe7]Bradykinin and [Thi6,9,D-Phe8]Kallidin are pure antagonists, the second one showing little BK-like activity on three of the four preparations. The kallidin analogue is more potent in all preparations than the bradykinin one. The two [Thi5,8,D-Phe7]BK (that supplied by J.-M. Stewart and that prepared in our laboratory) show very similar affinities in all preparations. The bradykinin analogue as well as the kallidin one are also active against desArg9-bradykinin in the rabbit aorta, at concentrations similar to those active on B2 receptor systems. The kinin antagonists are however specific for the kinins, since they do not interfere with the myotropic effects of angiotensin or substance P (SP) in the various preparations.
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Denault JB, Claing A, D'Orléans-Juste P, Sawamura T, Kido T, Masaki T, Leduc R. Processing of proendothelin-1 by human furin convertase. FEBS Lett 1995; 362:276-80. [PMID: 7729512 DOI: 10.1016/0014-5793(95)00249-9] [Citation(s) in RCA: 71] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Endothelin-1 (ET-1) is the most potent vasoactive peptide known to date. The peptide is initially synthesized as an inactive precursor (proET-1) which undergoes proteolysis at specific pairs of basic amino acids to yield bigET-1. Production of ET-1 then proceeds by cleavage of bigET-1 by the endothelin converting enzyme (ECE). Here, we demonstrate that the in vitro cleavage of proET-1 by furin, a mammalian convertase involved in precursor processing, produced bigET-1. Upon further processing, bigET-1 was converted to biologically active ET-1. Furthermore, we demonstrate that the furin inhibitor, decanoyl-Arg-Val-Lys-Arg chloromethylketone, abolished production of ET-1 in endothelial cells.
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Regoli D, D'Orléans-Juste P, Escher E, Mizrahi J. Receptors for substance P. I. The pharmacological preparations. Eur J Pharmacol 1984; 97:161-70. [PMID: 6200335 DOI: 10.1016/0014-2999(84)90447-3] [Citation(s) in RCA: 69] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
The undecapeptide substance P (SP) is both a potent stimulant of intestinal (guinea pig ileum), vascular venous (rabbit mesenteric vein) and tracheal (guinea pig trachea) smooth muscles, and a relaxant of large arteries (dog common carotid artery, rabbit aorta). SP also decreases the peripheral vascular resistance in the coronary vessels of rabbit isolated hearts. The contractions of the guinea pig ileum in response to SP are partially antagonised by atropine and significantly depressed by indomethacin, while the contractions of the guinea pig trachea are strongly potentiated by indomethacin. Large arteries, but not the veins, are insensitive to SP when the endothelium is removed, and slightly less responsive to the peptide when this is applied in the presence of mepacrine, eicosatetraynoid acid or BW 755C. These results indicate that all myotropic actions of SP, except that on venous smooth muscle, are partially or completely indirect and most of them are due to the release of endogenous agents: these are acetylcholine, prostaglandins and possibly histamine in the guinea pig ileum, prostaglandins and possibly a leukotriene in the guinea pig trachea and a still unidentified factor of endothelial origin in dog and rabbit large arteries. The effect of substance P on the rabbit isolated anterior mesenteric vein appears to be a direct one.
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D'Orléans-Juste P, Plante M, Honoré JC, Carrier E, Labonté J. Synthesis and degradation of endothelin-1. Can J Physiol Pharmacol 2003; 81:503-10. [PMID: 12839262 DOI: 10.1139/y03-032] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The endothelin-converting enzyme (ECE) is the main enzyme responsible for the genesis of the potent pressor peptide endothelin-1 (ET-1). It is suggested that the ECE is pivotal in the genesis of ET-1, considering that the knockout of both genes generates the same lethal developments during the embryonic stage. Several isoforms of the ECE have been disclosed, namely ECE-1, ECE-2, and ECE-3. Within each of the first two groups, several sub-isoforms derived through splicing of single genes have also been identified. In this review, the characteristics of each sub-isoform for ECE-1 and 2 will be discussed. It is important to mention that the ECE is, however, not the sole enzyme involved in the genesis of endothelins. Indeed, other moieties, such as chymase and matrix metalloproteinase II, have been suggested to be involved in the production of ET intermediates, such as ET-1 (1-31) and ET-1 (1-32), respectively. Other enzymes, such as the neutral endopeptidase 24-11, is curiously not only involved in the degradation and inactivation of ET-1, but is also responsible for the final production of the peptide via the hydrolysis of ET-1 (1-31). In this review, we will attempt to summarize, through the above-mentioned characteristics, the current wisdom on the role of these different enzymes in the genesis and termination of effect of the most potent pressor peptide reported to date.
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Regoli D, Escher E, Drapeau G, D'Orléans-Juste P, Mizrahi J. Receptors for substance P. III. Classification by competitive antagonists. Eur J Pharmacol 1984; 97:179-89. [PMID: 6200337 DOI: 10.1016/0014-2999(84)90449-7] [Citation(s) in RCA: 64] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
A series of ten octa- and five undecapeptide antagonists of SP have been tested in four isolated smooth muscle preparations in order to characterise the receptors mediating the SP-induced contractions of the guinea pig ileum (G.P.I.), the guinea pig trachea (G.P.T.) and the rabbit mesenteric vein (R.M.V.) and the relaxation of the dog carotid artery (D.C.A.). It has been shown that: (a) Indirect effects by substance P and related peptides, mediated by acetylcholine or prostaglandins reduce the affinity of [pro4,trp7,9,10]SP (4-11) (an SP-antagonist) only in the G.P.I. (b) Octapeptide antagonists are specific for SP, have no agonistic activities and exert a competitive antagonism against SP, its homologues and fragments. (c) Undecapeptide antagonists are weaker than the octapeptides in the G.P.I. and G.P.T. and slightly stronger in the D.C.A. and R.M.V. However these compounds still have variable degrees of agonistic activity in some tissues. Affinity of octapeptide antagonists bearing the basic structure [pro4,trp7,9]SP-(4-11) is increased by the additional replacement of Leu10 with trp, Met11 with Leu, Nle or Phe, but it is slightly reduced by substituting Phe8 with Val. Antagonists containing aliphatic residues at the C-terminal end, for instance [pro4,trp7,9,Nle11]SP-(4-11) are more potent than others in the R.M.V., while those with aromatic residues, for instance [pro4,trp7,9,10]SP-(4-11) are weak on the R.M.V. but fairly active on the G.P.T. These antagonists do not show any selectivity on the G.P.I. and the D.C.A. Comparison of antagonists affinities for receptor characterisation suggest the existence of three different functional sites for SP-related peptides. The site of the G.P.I. and D.C.A., which accepts both the antagonists containing aromatic or aliphatic groups at the C-terminal end; the site of the G.P.T. which prefers the aromatic and that of the R.M.V. which shows high affinity for aliphatic residues. The receptor classification emerging from data obtained with antagonists is compared with the classifications of the literature and with those based on the order of potencies of SP homologues and fragments.
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Rhaleb NE, Rouissi N, Nantel F, D'Orléans-Juste P, Regoli D. DuP 753 is a specific antagonist for the angiotensin receptor. Hypertension 1991; 17:480-4. [PMID: 1672862 DOI: 10.1161/01.hyp.17.4.480] [Citation(s) in RCA: 64] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
2-n-Butyl-4-chloro-5-hydroxy-methyl-1-[(2'-(1H)-tetrazol-5-yl)biph enyl-4- yl)methyl]imidazol potassium salt (DuP 753) is a nonpeptide angiotensin II receptor antagonist that inhibits the contractile effects of angiotensin II competitively and shows pA2 values of 8.27 on the rabbit aorta and jugular vein, 8.66 on the rat portal vein and stomach, 8.19 on the rat urinary bladder, and 8.36 on human colon, ileum, and urinary bladder. This agent (more than 10(-5) M) exhibits no agonistic activity and does not affect the contractile effects of norepinephrine, acetylcholine, bradykinin, desArg9-bradykinin, substance P, neurokinin A, neurokinin B, or bombesin in the various tissues. The present results demonstrate that DuP 753 is a potent nonpeptide antagonist with high affinity, specificity, and selectivity for the angiotensin receptor.
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Bkaily G, Sleiman S, Stephan J, Asselin C, Choufani S, Kamal M, Jacques D, Gobeil F, D'Orléans-Juste P. Angiotensin II AT1 receptor internalization, translocation and de novo synthesis modulate cytosolic and nuclear calcium in human vascular smooth muscle cells. Can J Physiol Pharmacol 2003; 81:274-87. [PMID: 12733826 DOI: 10.1139/y03-007] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The present study was designed to verify if human (h) Angiotensin II (Ang II) type-1 receptor (hAT1R) undergoes internalization, nuclear translocation, and de novo synthesis in primary culture of human aortic vascular smooth muscle cells (hVSMCs) and if overexpression of this receptor modulates sustained free cytosolic ([Ca]c) and nuclear ([Ca]n) calcium. 3-dimensional (3-D) confocal microscopy was used to monitor free intracellular Ca2+ and hAT1R-green fluorescence protein (GFP) fusion protein in cultured hVSMCs. Immunofluorescence studies showed the presence of hAT1R and the absence of hAT2R in normal hVSMCs. Using 3-D imaging technique, hAT1 receptors were localized at the sarcolemma and in the cytosolic and nuclear compartments. In native as well as in normal hAT1R or hAT1R-GFP overexpressing hVSMCs, Ang II (10(-9) and 10(-4) M) induced internalization and nuclear translocation of this type of receptor. The internalization of hAT1Rs is mediated via clathrin-coated pits and vesicles pathway. This phenomenon of trancellular trafficking of receptors was associated with an increase of hAT1R. The Ang II induced increase of hAT1R density was prevented by the protein synthesis inhibitor cycloheximide. Overexpression of hAT1R and hAT1R-GFP decreased both basal cytosolic and nuclear Ca2+. In normal hVSMCs and low hAT1R-GFP overexpressing hVSMCs, Ang II (10(-15) to 10(-4) M) induced a dose-dependent sustained increase of [Ca]c and [Ca]n with an EC50 near 5 x 10(-11) and 5 x 10(-9) M, respectively. Our results suggest that hAT1Rs are the predominant type of Ang II receptors in aortic hVSMCs and are present in the sarcolemma, the cytosolic and the nuclear compartments. Ang II rapidly induces hAT1R internalization, nuclear translocation, as well as nuclear de novo synthesis of this receptor. The hAT1R overexpression in hVSMCs modulates sustained [Ca]c and [Ca]n.
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MESH Headings
- Aniline Compounds
- Aorta/cytology
- Aorta/metabolism
- Blotting, Western
- Calcium/metabolism
- Cell Nucleus/metabolism
- Cells, Cultured
- Fluorescent Antibody Technique
- Fluorescent Dyes
- Green Fluorescent Proteins
- Humans
- Luminescent Proteins/genetics
- Microscopy, Confocal
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/metabolism
- Receptor, Angiotensin, Type 1/genetics
- Receptor, Angiotensin, Type 1/metabolism
- Recombinant Fusion Proteins/metabolism
- Sarcolemma/physiology
- Transfection
- Translocation, Genetic
- Xanthenes
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Regoli D, Drapeau G, Rovero P, Dion S, Rhaleb NE, Barabé J, D'Orléans-Juste P, Ward P. Conversion of kinins and their antagonists into B1 receptor activators and blockers in isolated vessels. Eur J Pharmacol 1986; 127:219-24. [PMID: 2875891 DOI: 10.1016/0014-2999(86)90367-5] [Citation(s) in RCA: 54] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
A carboxypeptidase inhibitor (DL-2-mercaptomethyl-3-guanidoethylthiopropranoic acid) (mergetpa) was used to block the conversion of kinins and B2 receptor antagonists into metabolites devoid of the C-terminal Arg. Experiments were carried out on rabbit isolated aortae (a B1 receptor system) or rabbit jugular veins and dog carotid arteries (two B2 receptor systems). The contractile effect of bradykinin in the rabbit aorta was significantly reduced by mergetpa while that of desArg9-BK was not modified. pA2 values of B2 receptor antagonists, [Thi5,8,D-Phe7]bradykinin and [Thi6,9,D-Phe8]kallidin were markedly reduced by mergetpa. The apparent affinity (pA2) of a B1 receptor antagonist, [Leu9]desArg10-kallidin was not affected. Carboxypeptidases inhibition did not modify the activities of bradykinin or the affinities of B2 receptor antagonists in the rabbit jugular vein and the dog carotid artery. An inhibitor of kininase II (D-3-mercapto-2-methylpropranoyl-L-proline (S,S] (captopril) reduced the contractile effects of angiotensin I in the three preparations and potentiated the stimulatory or inhibitory effects of bradykinin: captopril did not have effect on the affinities of B2 receptor antagonists and did not modify the effects of angiotensin II. Comparative experiments performed in tissues with or without endothelium gave the same results with both mergetpa and captopril. The present findings suggest that bradykinin and B2 receptor antagonists are converted by carboxypeptidases into biologically active B1 receptor agonist or antagonists. This is the reason why B2 receptor antagonists are not selective.
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D'Orléans-Juste P, Claing A, Télémaque S, Warner TD, Regoli D. Neurokinins produce selective venoconstriction via NK-3 receptors in the rat mesenteric vascular bed. Eur J Pharmacol 1991; 204:329-34. [PMID: 1723050 DOI: 10.1016/0014-2999(91)90860-s] [Citation(s) in RCA: 52] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The vasoactive properties of the neurokinins (substance P (SP), neurokinin A (NKA), neurokinin B (NKB)) and some selective analogues were assessed in the arterial and venous mesenteric beds of the rat. Although both sides of the mesenteric vasculature displayed endothelium-dependent relaxation in response to acetylcholine (ACh) or bradykinin (BK) (1 and 10 nmol), SP and the selective NK-1 analogue, [Sar9,Met(O2)11]SP were inactive. Of the three selective neurokinin agonists used, [Sar9,Met(O2)11]SP (NK-1), [beta-Ala8]NKA-(4-10) (NK-2) and [MePhe7]NKB (NK-3), only the latter induced a dose-dependent pressor effect in the venous mesenteric vasculature. Injections of SP and the selective NK-1 and NK-2 analogues at high doses (10 nmol), did not change the perfusion pressure in the mesenteric bed even when the mesenteric vasculature was treated with methylene blue (50 microM) to inhibit the effects of endothelium-derived relaxing factor (EDRF) or with NG-nitro-L-arginine (L-NNA) (20 microM) to inhibit the formation of EDRF or with 3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonate] (CHAPS 20 mM, 30 s) to remove the endothelial layer. In contrast, the vasoconstrictor effects of noradrenaline (NA), angiotensin II (ATII), NKB and [MePhe7]NKB on the venous side of the circulation were enhanced following treatment with L-NNA, methylene blue or CHAPS. The present results suggest that neurokinins act on the rat mesenteric bed by increasing the perfusion pressure of the venous vasculature via activation of NK-3 receptors. Neurokinins are inactive on the arterial mesenteric vasculature.(ABSTRACT TRUNCATED AT 250 WORDS)
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Gratton JP, Cournoyer G, Löffler BM, Sirois P, D'Orléans-Juste P. ET(B) receptor and nitric oxide synthase blockade induce BQ-123-sensitive pressor effects in the rabbit. Hypertension 1997; 30:1204-9. [PMID: 9369277 DOI: 10.1161/01.hyp.30.5.1204] [Citation(s) in RCA: 51] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Endothelin-1 (0.25 nmol/kg, injected into the left cardiac ventricle) induces a protracted increase of mean arterial pressure that is significantly reduced by the selective ET(A) receptor antagonist BQ-123 (1 and 10 mg/kg) in the anesthetized rabbit. The sole administration of the selective ET(B) antagonist BQ-788 (0.25 mg/kg) induces a pressor response abolished by BQ-123 (1 mg/kg). Concomitant to the increase in mean arterial pressure, BQ-788 induces a significant increase in plasma levels of endothelin-1 and its precursor big endothelin-1. The nitric oxide synthase inhibitor N omega-nitro-L-arginine methyl ester (L-NAME; 10 mg/kg) also increases arterial blood pressure, and the response is reduced dose-dependently by BQ-123 (1 and 10 mg/kg). In addition, the administration of BQ-788 in the presence of L-NAME induced a further increase in arterial blood pressure. The duration of the pressor response to L-NAME is also significantly reduced by an endothelin-converting enzyme inhibitor, phosphoramidon (10 mg/kg). Finally, L-NAME induces an increase in plasma levels of big endothelin-1 but not endothelin-1. Our results illustrate that blockade of either nitric oxide synthase or ET(B) receptors triggers a raise in plasma levels of endothelin-1 or its precursor. These later moieties are suggested to be significantly involved, through the activation of ET(A) receptors, in the pressor effects of L-NAME and BQ-788 in the anesthetized rabbit.
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D'Orléans-Juste P, Claing A, Télémaque S, Maurice MC, Yano M, Gratton JP. Block of endothelin-1-induced release of thromboxane A2 from the guinea pig lung and nitric oxide from the rabbit kidney by a selective ETB receptor antagonist, BQ-788. Br J Pharmacol 1994; 113:1257-62. [PMID: 7889281 PMCID: PMC1510539 DOI: 10.1111/j.1476-5381.1994.tb17133.x] [Citation(s) in RCA: 49] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
1. The present study characterizes the receptors responsible for endothelin-1-induced release of thromboxane A2 from the guinea pig lung and of endothelium-derived nitric oxide from the rabbit perfused kidney, by the use of the selective ETA receptor antagonist, BQ-123, and a novel selective ETB receptor antagonist, BQ-788. 2. In the guinea pig perfused lung, endothelin-1 (ET-1) (5 nM) induced a marked increase of thromboxane A2 which was reduced by 17 +/- 5.0, 70 +/- 1.0 and 93 +/- 1.2% by BQ-788 infused at concentrations of 1, 5 and 10 nM respectively. In contrast, BQ-123 (0.1 and 1.0 microM) had little or no effect on the ET-1-induced release of thromboxane A2. 3. In the same perfused model, the selective ETB agonist, IRL 1620 (50 nM), stimulated the release of thromboxane A2, but not prostacyclin. The eicosanoid-releasing properties of IRL 1620 were abolished by BQ-788 at 10 nM, yet were unaffected by BQ-123 (1 microM). 4. In the rabbit perfused kidney, BQ-788 (10 nM) potentiated the increase of perfusion pressure induced by endothelin-1 (1, 5 and 10 nM) by approximately 90%, but not that induced by angiotensin II (1 microM). Furthermore, the selective ETB receptor antagonist did not reduce the release of prostacyclin triggered by either peptide. 5. In another series of experiments, pretreatment of the perfused kidney with a nitric oxide synthase inhibitor, L-NAME (100 microM), potentiated the pressor responses to both endothelin-1 and angiotensin II. Under L-NAME treatment, BQ-788 did not further potentiate the pressor response to endothelin-1. 6 Our results illustrate the predominant role of ETB receptor activation in the release of thromboxane A2 and nitric oxide triggered by endothelin-l in the guinea pig perfused lung and rabbit kidney respectively.
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Picher M, Sévigny J, D'Orléans-Juste P, Beaudoin AR. Hydrolysis of P2-purinoceptor agonists by a purified ectonucleotidase from the bovine aorta, the ATP-diphosphohydrolase. Biochem Pharmacol 1996; 51:1453-60. [PMID: 8630086 DOI: 10.1016/0006-2952(96)00086-x] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Pharmacologists are becoming more and more aware of the possibility that certain ATP analogues currently used to classify the P2-purinoceptors are dephosphorylated by ectonucleotidases. In this study, we provide evidence that in the vascular system, these purine analogues are hydrolysed by an ATP-diphosphohydrolase (ATPDase). This enzyme is known as the major plasma membrane nucleotidase of endothelial and smooth muscle cells, and is believed to dephosphorylate extracellular triphospho- and diphosphonucleosides. Assays were conducted with a purified ATPDase from smooth muscle cells of bovine aorta. At a concentration of 250 microM, adenosine 5'-(alpha,beta-methylene) triphosphonate (alpha,beta-metATP), adenosine 5'-(beta,gamma-methylene) triphosphonate (beta,gamma-metATP), adenosine 5'-(alpha,beta-methylene) disphosphonate (alpha,beta-metADP), adenylyl 5'-(beta,gamma-imido) diphosphonate (beta,gamma-imidoATP) and adenosine 5'-O-(2-thiodiphosphate) (ADP beta S) all resisted dephosphorylation, whereas 2-chloroadenosine triphosphate (2-chloroATP), 2-methylthioadenosine triphosphate (2-MeSATP) and 8-bromoadenosine triphosphate (8-bromo-ATP) were hydrolysed at 99, 63, and 20% of the rate of ATP hydrolysis, respectively. All the non-hydrolysable analogues tested, except alpha,beta-metADP, competed with ATP and ADP for the ATPDase catalytic site, reducing their hydrolysis by 35-50%. Apparent Km values for ATP and ADP were estimated at 14.1 and 12.0 microM, respectively, whereas apparent Km and Ki values for the purine analogues ranged from 12 to 28 microM. These results strongly support the view that (1) the ATPDase is expected to reduce substantially the P2-response induced by ATP, ADP, and some hydrolysable agonists; and (2) by competing with the hydrolysis of endogenously released ATP and ADP, non-hydrolysable analogues could alter the amplitude or direction of the cellular response induced by these natural substrates.
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Fabricio AS, Silva CA, Rae GA, D'Orléans-Juste P, Souza GE. Essential role for endothelin ET(B) receptors in fever induced by LPS (E. coli) in rats. Br J Pharmacol 1998; 125:542-8. [PMID: 9806338 PMCID: PMC1565640 DOI: 10.1038/sj.bjp.0702075] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
1. The influence of endothelin receptor antagonists on febrile responses to E. coli lipopolysaccharide (LPS), interleukin-1beta (IL-1beta), tumour necrosis factor-alpha (TNF-alpha) and endothelin-1 (ET-1) was assessed in conscious rats. 2. Intravenous (i.v.) LPS (5.0 microg kg(-1)) markedly increased rectal temperature to a peak of 1.30 degrees C over baseline at 2.5 h. Pretreatment with the mixed endothelin ET(A)/ET(B) receptor antagonist bosentan (10 mg kg(-1), i.v.) or the selective endothelin ET(B) receptor antagonist BQ-788 (N-cis-2,6-dimethylpiperidinocarbonyl-L-gamma-methylleucyl-D -1-methoxycarboyl-D-norleucine; 3 pmol, into a lateral cerebral ventricle-i.c.v.) reduced the peak response to LPS to 0.90 and 0.75 degrees C, respectively. The selective endothelin ET(A) receptor antagonist BQ-123 (cyclo[D-Trp-D-Asp-Pro-D-Val-Leu]; 3 pmol, i.c.v.) was ineffective. 3. Increases in temperature caused by IL-1beta (180 fmol, i.c.v.), TNF-alpha (14.4 pmol, i.c.v.) or IL-1beta (150 pmol kg(-1), i.v.) were unaffected by BQ-788 (3 pmol, i.c.v.). 4. Central injection of endothelin-1 (0.1 to 3 fmol, i.c.v.) caused slowly-developing and long-lasting increases in rectal temperature (starting 2 h after administration and peaking at 4-6 h between 0.90 and 1.15 degrees C) which were not clearly dose-dependent. The response to endothelin-1 (1 fmol, i.c.v.) was prevented by BQ-788, but not by BQ-123 (each at 3 pmol, i.c.v.). Intraperitoneal pretreatment with the cyclo-oxygenase inhibitor indomethacin (2 mg kg(-1)), which partially reduced LPS-induced fever, did not modify the hyperthermic response to endothelin-1 (3 fmol, i.c.v.). 5. Therefore, central endothelin(s) participates importantly in the development of LPS-induced fever, via activation of a prostanoid-independent endothelin ET(B) receptor-mediated mechanism possibly not situated downstream from IL-1beta or TNF-alpha in the fever cascade.
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Gendron FP, Halbfinger E, Fischer B, Duval M, D'Orléans-Juste P, Beaudoin AR. Novel inhibitors of nucleoside triphosphate diphosphohydrolases: chemical synthesis and biochemical and pharmacological characterizations. J Med Chem 2000; 43:2239-47. [PMID: 10841802 DOI: 10.1021/jm000020b] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
To elucidate the physiological role played by nucleoside triphosphate diphosphohydrolase (NTPDase; EC 3.6.1.5), adenine nucleotide analogues, modified on the purine ring, have been synthesized and tested as potential inhibitors. Resistance of ATP analogues to hydrolysis and their potency as NTPDase inhibitors were evaluated. For this purpose, a particulate fraction isolated from bovine spleen was used as the enzyme source. Among the synthesized analogues, 8-thiobutyladenosine 5'-triphosphate (8-BuS-ATP) was found to be the most effective nonhydrolyzable competitive inhibitor, with an estimated K(i) of 10 microM. This nonhydrolyzable analogue did not exert any P2X-receptor-mediated effect on endothelium-denuded blood vessels, from the guinea pig mesenteric bed. In agreement with this observation, infusion of the analogue did not cause any significant blood pressure variations of the precontracted vessel. Because in previous studies on isolated turkey erythrocytes and rat astrocytes 8-BuS-ATP was not able to trigger any P2Y(1)-receptor-mediated effect, it therefore appears that this NTPDase inhibitor does not interfere with purinergic receptors.
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Mizrahi J, Dion S, D'Orléans-Juste P, Escher E, Drapeau G, Regoli D. Tachykinin receptors in smooth muscles: a study with agonists (substance P, neurokinin A) and antagonists. Eur J Pharmacol 1985; 118:25-36. [PMID: 2417867 DOI: 10.1016/0014-2999(85)90659-4] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Four preparations, sensitive to tachykinins, the guinea-pig urinary bladder, the rat duodenum, the hamster and dog urinary bladders have been investigated and compared with four other preparations described before: the guinea-pig ileum and trachea, the dog carotid artery and the rabbit mesenteric vein. On the basis of the order of potency of agonists, evaluated with substance P, physalaemin, eledoisin, kassinin and neurokinin A, the preparations can be separated into three groups, the guinea-pig urinary bladder and the dog carotid artery, in which substance P is the most potent and neurokinin A the weakest tachykinin, the rabbit mesenteric vein, the guinea-pig trachea and the rat duodenum, in which the opposite order is observed and the hamster and dog urinary bladders, in which kassinin is the most potent agonist. The guinea-pig ileum shows similar sensitivity to the five tachykinins. C-terminal partial sequences appear to be weaker than SP-(1-11) in three of the four new preparations, SP-(6-11) being first in the rat duodenum and slightly weaker than SP-(1-11) in the hamster and dog urinary bladders. Studies performed with antagonists or inhibitors of endogenous agents suggest that substance P and neurokinin A act directly on specific receptors. The effects of the two peptides are reduced by antagonists analogues of the sequence SP-(4-11). One of the antagonists, [D-Pro4,Lys6,D-Trp7,9,10, Phe11]SP-(4-11) has been shown to be competitive against substance P and neurokinin A in the guinea-pig ileum, the guinea-pig urinary bladder and the rat duodenum. This compound, shows definitely higher activity against neurokinin A and kassinin, compared to substance P in various preparations. [D-Tyr4,D-Trp7,9,Nle11]SP-(4-11) is the most potent tachykinin antagonist in the hamster and dog urinary bladders. In these preparations, the antagonists act also against substance P, but with lower affinity. These findings with antagonists support the indication, emerged from the order of potency of agonists, that tachykinins may act on two and possibly three different receptor types.
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