• Title, Summary, Keyword: tachykinin

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Solution Structure of Neuropeptide $\gamma$ from Carassius auratus by NMR spectroscopy

  • Lee, Sangwon;Park, Namgyu;Kim, Yangmee
    • Proceedings of the Korean Biophysical Society Conference
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    • pp.31-31
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    • 1999
  • Neuropeptide ${\gamma}$ is a recently identified tachykinin family peptide which has conserved ammo acid sequence of -Phe-X-Gly-Leu-Met-NH2 in the C-terminal region, where X represents aromatic or hydrophobic residues. In this study, three-dimensional structure of neuropeptide ${\gamma}$ from goldfish Carassius auratus (G-NP${\gamma}$) was determined by NMR spectroscopy.(omitted)

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Structure-Antagonistic Activity Relationships of an NK-2 Tachykinin Receptor Antagonist, L-659,877 and Its Analogues

  • Ha, Jong-Myung;Shin, Song-Yub;Hong, Hea-Nam;Suh, Duk-Joon;Jang, Tae-Sik;Kang, Shin-Won;Kuean, Sun-Jin;Ha, Bae-Jin
    • BMB Reports
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    • v.29 no.5
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    • pp.429-435
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    • 1996
  • To investigate the structure-antagonistic relationship of the cyclohexapeptide L-659,877, a selective NK-2 tachykinin receptor antagonist, seven analogues were chemically synthesized by a solid phase method. The agonistic and antagonistic activities of the analogues were evaluated by contraction assay using the smooth muscle of guinea pig trachea (GPT) containing the NK-2 receptor. It was shown that the aromatic ring of Phe at position 3 and the sulfur group of Met at position 6 in L-659,877 were essential for binding to the NK-2 receptor. Decrease in antagonistic activity of L-659,877 caused by substituting Leu for Nle at position 5 indicates that the ${\gamma}$ methyl group and side chain length of Leu plays an important role in its antagonistic action. Although the activity was slightly lower than L-659,877, cyclo $[{\beta}Ala^{8}]NKA(4-10)$ (analogue 1) showed potential antagonistic activity for the NK-2 receptor. It was confirmed that the expansion of the ring in L-659,877 by substitution of ${\beta}Ala$ for Gly at position 4 stabilized its conformation monitored by CD spectra. The results suggest that analogue 1 can be used as a new leader compound to design a more powerful, selective, and stable NK-2 receptor antagonist.

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Effects of Tachykinins on Intestinal Smooth Muscle of Nile tilapia(Oreochromis niloticus) and Israel carp(Cyprinus carpio) (나일틸라피아(Oreochromis niloticus)와 이스라엘잉어(Cyprinus carpio)의 장관 평활근의 수축활성에 미치는 Tachykinin류의 영향)

  • Kim, Eun-Hee;Seo, Jung-Soo;Huh, Min-Do;Park, Nam-Gyu;Lee, Hyung-Ho;Chung, Joon-Ki
    • Journal of fish pathology
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    • v.14 no.1
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    • pp.46-53
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    • 2001
  • The present study was undertaken to investigate and compare the effect and mode of action of tachykinins on isolated strip preparations of the intestinal smooth muscle from the nile tilapia, Oreochromis niloticus and the Israel carp, Cyprinus carpio. Both of neurokinin 1(NK-1) receptor agonist, substance P(SP) and neurokinin 2(NK-2) receptor agonist, neurokinin A(NKA) caused concentration-dependent contractions of intestinal smooth muscle in the nile tilapia and the israel carp. The efficiency and potency of these agonists varied between two fish species. In the nile tilapia intestine, the efficiency and potency of SP were greater than those of NKA. However, the efficiency and potency of SP were similar to those of NKA. In the nile tilapia intestine and the israel carp intestine, the contractile responses of SP and NKA were noncompetitively antagonized by NK-1 receptor antagonist, L-732, 138 but unaffected by NK-2 receptor antagonist, MDL 29913. In addition, SP-induced contractions in the both of preparation were significantly inhibited by muscarinic antagonist, atropine($5{\times}10^{-7}$M) and ganglionic inhibitor, tetrodotoxin($2{\times}10^{-7}$M) but NKA-induced contractions were unaffected by those. These results indicate that two tachykinin agonists, SP and NKA predominately modulate the mechanical activity of isolated preparation from the nile tilapia and the israle carp directly through the activation of NK-1 receptor on the intestinal smooth muscle cells, but in the case of SP action, the indirect action through activation of cholinergic nerve terminals seems to be also implicated.

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Neurotoxic Desensitizing Effect of Capsaicin on Peripheral Sensory Nerve Endings in Guinea Pig Bronchi (기니픽 기관지 말초신경에 대한 캡사이신의 탈감작 효과)

  • Jung, Yi-Sook;Cho, Tai-Soon;Moon, Chang-Hyun;Shin, Hwa-Sup
    • YAKHAK HOEJI
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    • v.41 no.1
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    • pp.139-146
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    • 1997
  • In the present study, capsaicin-induced desensitization of peripheral sensory nerves were investigated by using guinea pig bronchi, in which these nerves are stimulated with cap saicin to produce a contractile response via the release of sensory neuropeptides such as substance P and neurokinin A. The contractile response to capsaicin was inhibited by the combination of CP96345 and SR 48968 suggesting that the excitatory effect of capsaicin is mediated via both the tachykinin NK-1 and NK-2 receptor. Capsaicin produced in vitro-desensitization in dose-dependent manner, but after this in vitro-desensitization the response to NK-1 and NK-2 receptor agonist did not change. Systemic administration (s.c.) of capsaicin also desensitized significantly bronchial tissues but could not produce any change in the contractile response to the selective agonists of NK-1 and NK-2 receptor. Therefore, the present results suggest that functional desensitization to capsaicin-induced contractile response in guinea pig bronchi does not involve NK-1 and NK-2 receptor, while excitatory effect of capsaicin is mediated via both NK-1 and NK-2 receptor. In conclusion, it is suggested that capsaicin- induced excitation and desensitization involves somewhat different pathways.

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Effects of Substance P on the Cell Proliferation and IL-2 Production of T Lymphocyte (Substance P가 T 임파구의 세포증식과 IL-2 생산에 미치는 영향)

  • Moon, Jin-Kyun;Choi, Byung-Son;Lee, Seok-Cho;Kim, Hyung-Seop
    • Journal of Periodontal and Implant Science
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    • v.27 no.4
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    • pp.805-818
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    • 1997
  • Immune responses of periodontal tissue may be regulated by products of sensory afferent nerve endings such as neuropeptides. Substance P(SP), a tachykinin neuropeptide, has been previously reported to stimulate the activities of T lymphocyte. Therefore, I examined the role of SP in IL-2 production and cell proliferation by using a homogeneous line of T lymphocytes(Jurkat and HuT78). Cell proliferation rate was determined by [$^3H$]-thymidine incorporation test, and IL-2 was quantitated by the growth rate of CD4+ IL-2-dependent T lymphocyte line CTLL-2. SP stimulated cell proliferation of T lymphocytes at the concentration of $10^{-12}$ and $10^{-8}$M in a biphasic bell-shape dose-dependent manner. However, SP alone did not induce IL-2 release at the concentration range of $10^{-6}$ to $10^{-14}$M. The upregulation of IL-2 release was observed when $10^{-12}$M SP was applied together with mitogens such as Con A or PHA+PMA on T cell lines, especially on Jurkat. Con A or PHA+PMA demonstrated to increase the rate of cell proliferation of Jurkat, which had shown to produce much amount of IL-2 indicating that mitogen-induced cell proliferation might be partially influenced by released IL-2. It was concluded that regulatory effects of SP on the immune/inflammatory response could be mediated through the costimulatory upregulation of IL-2 production and increase of cell proliferation of T lymphocyte.

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Conformation of cyclo-[Gln-Trp-Phe- $\beta$Ala-Leu-Met], a NK-2 Tachykinin Receptor Antagonist (NK-2의 Antagonist인 cyclo-[Gln-Trp-Phe- $\beta$Ala-Leu-Met]의 형태에 관한 연구)

  • Ha, Jong Myung
    • Journal of the Korean Chemical Society
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    • v.43 no.5
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    • pp.540-546
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    • 1999
  • Solution conformation of cyclo-($Gln^1-Trp^2-Phe^3-{\beta}Ala^4-Leu^5-Met^6$), new NK-2 antagonist in dimethyl sulfoxide solution, has been determined by the use of two-dimensional nuclear magnetic resonance spectroscopy combined with simulated annealing calculations. The peptide exhibited converged structures with the atomic root-mean-square difference for the backbone atoms ($N,\;C^{\alpha},\;C'$) of all residues being 0.02${\AA}$ in the 25 annealed structures. The analysis of the structures indicated that the cyclic peptide has three intramolecular hydrogen bonds between $Met^6NH$ and ${\beta}Ala^4CO$, ${\beta}Ala^4NH$ and $Met^6CO$, $Phe^3NH$ and $Met^6CO$, and contain a type-I ${\beta}$-turn with Gln and Trp and ${\gamma}$-turn with Leu. The addition of an extra methylene group to Gly, i.e. P-Ala residue, may relax some unfavorable restraints in the cyclic backbone structure, hence enabling an additional hydrogen bond, which results in stabilizing one conformation.

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Neurokinin B-related Peptide Suppresses the Expression of GnRH I, Kiss2 and tac3 in the Brain of Mature Female Nile tilapia Oreochromis niloticus

  • Jin, Ye Hwa;Park, Jin Woo;Kim, Jung-Hyun;Kwon, Joon Yeong
    • Development and Reproduction
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    • v.20 no.1
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    • pp.51-61
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    • 2016
  • Neurokinin B (NKB) and neurokinin B related peptide (NKBRP) belong to tachykinin peptide family. They act as a neurotransmitter and/or neuromodulator. Mutation of NKB and/or its cognate receptor, NK3R resulted in hypogonadotropic hypogonadism in mammals, implying a strong involvement of NKB/NK3R system in controlling mammalian reproduction. Teleosts possess NKBRP as well as NKB, but their roles in fish reproduction need to be clarified. In this study, NKB and NKBRP coding gene (tac3) was cloned from Nile tilapia and sequenced. Based on the sequence, Nile tilapia NKB and NKBRP peptide were synthesized and their biological potencies were tested in vitro pituitary culture. The synthetic NKBRP showed direct inhibitory effect on the expression of GTH subunits at the pituitary level. This inhibitory effect was confirmed in vivo by means of intraperitoneal (ip) injection of synthetic NKB and NKBRP to mature female tilapia (20 pmol/g body weight [BW]). Both NKB and NKBRP had no effect on the plasma level of sex steroids, E2 and 11-KT. However, NKBRP caused declines of expression level of GnRH I, Kiss2 and tac3 mRNAs in the brain while NKB seemed to have no distinct effect. These results indicate some inhibitory roles of NKBRP in reproduction of mature female Nile tilapia, although their exact functions are not clear at the moment.

Nonadrenergic Noncholinergic Nerve-mediated Contraction of the Longitudinal Muscle of Rat Ileum (랫드 회장 종주근의 비아드레날린 비콜린성 신경에 의한 수축반응)

  • Kim, Tae-wan;La, Jun-ho;Sung, Tae-sik;Kang, Jung-woo;Yang, Il-suk;Han, Ho-jae
    • Korean Journal of Veterinary Research
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    • v.43 no.3
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    • pp.405-414
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    • 2003
  • The purpose of this study was to assess the role of tachykinins (TK) in mediating nonadrenergic noncholinergic (NANC) contractions produced by electrical field stimulation (EFS) in the longitudinal muscle of the rat ileum. In the presence of atropine ($1{\mu}M$), guanethidine ($5{\mu}M$), and L-nitroarginine (L-NNA, $200{\mu}M$), EFS (0.5ms pulse duration, 120 V, 1-20 Hz for 2 min) produced a frequency-dependent slowly-developing tonic contraction with superimposed phasic contractions ('on'-contraction) followed by off slowly-decreasing tonic and superimposed phasic contractions ('off'-contraction) of mucosa-free longitudinal oriented muscle strip. These EFS induced responses were blocked by tetrotoxin. $NK_1$ receptor selective antagonist L-732,138 strongly inhibited the EFS-induced excitatory responses. However $NK_2$ receptor selective antagonist, GR 159897 and $NK_3$ receptor selective antagonist SB 222200 did not significantly inhibited the responses. $NK_1$ receptor selective agonist [$Sar^9$,$Met(O_2)^{11}$] Substance P and $NK_2$ receptor selective agonist [${\beta}-Ala^8$]-neurokinin A (4-10) induced tonic contraction with superimposed phasic contractions of longitudinal oriented muscle strip and almost blocked by selective antagonist L-732,138 and GR 159897, respectively. But $NK_3$ receptor selective agonist senktide did not showed any effect. Nifedipine ($1{\mu}M$) abolished the contraction produced either by EFS or by the TK receptor agonists [$Sar^9$,$Met(O_2)^{11}$] Substance P or [${\beta}-Ala^8$]-neurokinin A (4-10). It is concluded that, in the longitudinal muscle of rat ileum, both $NK_1$ and $NK_2$ receptors modulated the responses to exogenous tachykinins, whereas $NK_1$ is mainly involved in NANC neuromuscular contraction.