Porcine Motilin Research Articles

Synthesis of the hexadecapeptide corresponding to positions 1 through 16 of porcine motilin, a gastric motor activity stimulating polypeptide.

The hexadecapeptide corresponding to positions 1 to 16 of porcine motilin was synthesized in a conventional manner. The synthetic peptide exhibited the activity of 3% of that of the synthetic motilin, when tested using rabbit duodenal muscle in vitro.

Synthesis of Porcine Motilin by Fragment Condensation Using Three Protected Peptide Fragments

Abstract Synthesis of porcine motilin is described. Construction of the entire molecule of this hormone was carried out by the fragment condensation method in solution employing Rudinger’s azide modification, and the resulting protected docosapeptide was deblocked by sodium–liquid ammonia procedure. Purification of the final product was performed by ion exchange chromatography on CM-Sephadex using ammonium acetate as eluent and gel filtration on BiO–Gel P-6. Purity of the synthetic docosapeptide was assessed by TLC in two different solvent systems and amino acid analysis. This polypeptide showed gastric motoractivity stimulating action on 30 min intravenous infusion in dogs in 5 ng/kg/min doses, which is characteristic to porcine motilin.

Synthesis of Protected Peptide Fragments Related to Porcine Motilin

Abstract Syntheses are described of three protected peptide fragments which correspond to positions 1–6, 7–11, and 12–22, respectively, of the entire amino acid sequence of porcine motilin, a gastric motoractivity-promoting polypeptide. Stable tosyl group was used for the protection of ε-amino group of lysine and guanidino group of arginine. These protected peptide fragments were mainly constructed in step wise manner using benzyloxycarbonyl amino acid by mixed anhydride method in the presence of N-hydroxysuccinimide. For preparation of the C-terminal undecapeptide, fragment condensation method was employed using two protected tripeptide azides. The protected peptides and intermediates could be readily purified by simple procedure.

Gastroduodenal Motor Response to Natural Motilin and Synthetic Position 13-Substituted Motilin Analogues: A Comparative In Vitro Study

Motor effects of graded concentrations of pure natural porcine motilin (13-Met-M) and synthetic motilin analogues - the methionine in position 13 substituted with either norleucine (13-Nle-M) or leucine (13-Leu-M) - on the rabbit, guinea-pig, rat, and human gastrointestinal smooth muscle were examined in vitro. Congruent species specificity of the motor activity of the motilins under study could be demonstrated in that muscle strips from rabbit and man were highly sensitive, whereas guinea-pig and rat preparations proved refractory to the polypeptides. In rabbit duodenal muscle and fundic muscle of the human stomach, graded concentrations of 13-Met-M, 13-Nle-M, and 13-Leu-M, respectively, produced graded increases in the contractile responses. The concentration-response curves were superimposable. Calculated maximal contractile responses (CMR's) and polypeptide doses for one-half maximal responses (D50 values) were not significantly different between the three motilins. Moreover, pharmacological analysis revealed that the motor effects of 13-Met-M, 13-Nle-M, and 13-Leu-M are uniformly not mediated via nervous pathways: neither blockage of axonal conduction by tetrodotoxin nor anticholinergic action by atropine exerted any detectable influence. Viewing the data presented, one may conclude that in man and rabbit, 1) natural porcine motilin and its synthetic position 13-substituted analogues, 13-Nle-M and 13-Leu-M, are of equal efficacy for gastroduodenal motor activity, and 2) position 13 of the amino acid sequence of motilin (22-residue chain) is not pertinent to the active site of the molecule.

Letter: Diphenyl phosphorazidate (DPPA) and diethyl phosphorocyanidate (DEPC). Two new reagents for solid-phase peptide synthesis and their application to the synthesis of porcine motilin.

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTDiphenyl phosphorazidate (DPPA) and diethyl phosphorocyanidate (DEPC). Two new reagents for solid-phase peptide synthesis and their application to the synthesis of porcine motilinShunichi Yamada, Nobuo Ikota, Takayuki Shioiri, and Shinro TachibanaCite this: J. Am. Chem. Soc. 1975, 97, 24, 7174–7175Publication Date (Print):November 1, 1975Publication History Published online1 May 2002Published inissue 1 November 1975https://doi.org/10.1021/ja00857a042RIGHTS & PERMISSIONSArticle Views639Altmetric-Citations58LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (316 KB) Get e-Alerts Get e-Alerts

ChemInform Abstract: SYNTHESIS OF THE DOCOSAPEPTIDE CORRESPONDING TO THE ENTIRE AMINO‐ACID SEQUENCE OF PORCINE MOTILIN

The docosapeptide corresponding to the entire amino-acid sequence of porcine motilin, a gastric motor activity-stimulating polypeptide, has been synthesised.

Radioimmunoassay for Motilin

A specific radioimmunoassay for motilin has been developed with the use of antisera to porcine motilin raised in guinea pigs. Highly purified 125-I-motilin was used as the tracer and the sensitivity range was 10 to 320 pg. No cross-reactivity was demonstrated with gastric inhibitory polypeptide, secretin, glucagon, gastrin, cholecystokinin-pancreozymin, or vasoactive intestinal peptide. In dogs with denervated pouches of the fundus of the stomach and Mann-Bollman fistulae, duodenal alkalinization resulted in an increase in gastric motor activity in the fundic pouch with a corresponding increase in serum motilin.

Studies on peptides. LV. Total synthesis of porcine motilin, a gastric motor activity stimulating polypeptide.

Synthesis of the docosapeptide corresponding to the newly revised sequence of porcine motilin, a gastric motor activity stimulating polypeptide, was accomplished. Synthetic peptide exhibited characteristic contractile activity patterns of the stomach and the duodenum in dogs, which were quite similar to those of the burst activity of these organs.

Studies on peptides. LIV. Synthesis of the protected tetradecapeptide corresponding to positions 9 through 22 of porcine motilin, a gastric motor activity stimulating polypeptide.

The protected tetradecapeptide corresponding to positions 9 through 22 of porcine motilin, Z (OMe)-Glu (OBzl)-Leu-Gln-Arg (Tos)-Met-Gln-Glu (OBzl)-Lys (Z)-Glu (OBzl)-Arg-(Tos)-Asn-Lys(Z)-Gly-Gln-OH, was synthesized to serve as a starting material for the total synthesis of this gastric motor activity stimulating polypeptide.

Synthesis of the docosapeptide corresponding to the entire amino-acid sequence of porcine motilin

The docosapeptide corresponding to the entire amino-acid sequence of porcine motilin, a gastric motor activity-stimulating polypeptide, has been synthesised.

Motilin, a gastric motor activity stimulating polypeptide: the complete amino acid sequence.

Porcine motilin is a 22 amino acid residue polypeptide with the amino acid sequence Phe–Val–Pro–Ile–Phe–Thr–Tyr–Gly–Glu–Leu–Gln–Arg–Met–Glu–Glu–Lys–Glu–Arg–Asn–Lys–Gly–Gln. The calculated molecular weight is 2700.