Biomedical subjects

T Sudoh

Publications and source records attributed to T Sudoh.

28 records · Page 2Linked to original sources

PubMed1990

[Preclinical evaluation of several cisplatinum analogs against human esophageal carcinoma by subrenal capsule assay].

The antitumor activities of CDDP analogs (CBD-CA, NK-121, 254-S) were evaluated preclinically by subrenal capsule assay (SRCA) with cyclophosphamide pretreatment. In the fundamental study, the antitumor activities against serially transplanted human esophageal cancer xenograft (IMEs-1) were compared with subcutaneous transplantation assay in nude mice and SRCA. The antitumor activities in SRCA were similar to those of in nude mice assay system (CBDCA greater than CDDP greater than 254-S greater than NK-121). Thus SRCA was considered to be useful for the evaluation of the activities of these agents. The activities were also tested against 10 human esophageal tumors obtained clinically. The sensitivity rate of these agents were 50% in CDDP, 30% in CBDCA, 30% in NK-121, and 30% in 254-S, respectively. These analogs seemed to be less effective than CDDP. However, in two cases, analogs were active though CDDP were inactive. The results suggest that these analogs are useful for the cases in which CDDP can not be given due to the toxicities and also for outpatient use.

Animals↗

PubMed1989

Cloning and sequence analysis of cDNA encoding a precursor for human brain natriuretic peptide.

Brain natriuretic peptide (BNP) is a novel diuretic-natriuretic and vasorelaxant peptide originally isolated from porcine brain. In contrast to mammalian atrial natriuretic peptide (ANP), immunological characterization suggests that mammalian BNPs show structural species differences. In order to determine the amino acid sequence of human BNP, we constructed a human cardiac atrium cDNA library and screened for clones hybridizing with porcine BNP cDNA. By sequence analysis of cDNA encoding a putative human BNP precursor, an amino acid sequence of human prepro-BNP of 134 residues has been deduced, in which a minimum bioactive unit highly homologous to porcine BNP-32 is present at the carboxy-terminus.

Amino Acid Sequence↗

PubMed1988

Cloning and sequence analysis of cDNA encoding a precursor for porcine brain natriuretic peptide.

Brain natriuretic peptide (BNP) is a new type of natriuretic peptide recently identified in porcine brain. Since the highest concentration of BNP was found in the cardiac atrium, the cDNA library of porcine cardiac atrium was constructed, and the cDNA clone encoding a BNP precursor was isolated and sequenced. The precursor for porcine BNP (porcine prepro-BNP) is 131 amino acids in length, including a 25 residue putative signal peptide at the N-terminus. Porcine BNP structure is located at the C-terminus of the precursor and is directly followed by a termination codon. Based on structural data recently obtained for gamma-BNP (a main storage form of BNP in the heart), prepro-BNP is processed to 106-residue gamma-BNP by removal of the signal peptide in the heart, and to low molecular weight forms, such as BNP-26 and BNP-32, in the brain.

Amino Acid Sequence↗

PubMed1988

Brain natriuretic peptide-32: N-terminal six amino acid extended form of brain natriuretic peptide identified in porcine brain.

Brain natriuretic peptide (BNP) is a newly identified peptide of 26 residues, which has a remarkable homology to but is distinct from atrial natriuretic peptide. The peptide exerts natriuretic-diuretic activity as well as potent chick rectum relaxant activity. By using radioimmunoassay specific to BNP and immunoaffinity chromatography, we have isolated from porcine brain a novel peptide of 32 residues carrying a BNP structure at the C-terminus. The amino acid sequence of this peptide was determined to be: Ser-Pro-Lys-Thr-Met- Arg-Asp-Ser-Gly-Cys-Phe-Gly-Arg-Arg-Leu-Asp-Arg-Ile-Gly-Ser-Leu-Ser-Gly- Leu- Gly-Cys-Asn-Val-Leu-Arg-Arg-Tyr. This peptide is an N-terminal six amino acid extended form of BNP and henceforth is designated BNP-32. BNP and BNP-32 are found to be major forms of BNP family in porcine brain.

Amino Acid Sequence↗

PubMed1988

Regional distribution of immunoreactive brain natriuretic peptide in porcine brain and spinal cord.

In order to elucidate the physiological functions of brain natriuretic peptide (BNP), radioimmunoassay for BNP was established and regional distribution of BNP in porcine brain and spinal cord was investigated. The concentration of immunoreactive (ir-) BNP in porcine whole brain was estimated to be 0.63 pmol/g, 13 times higher than that of ir-atrial natriuretic peptide (ANP). Highest concentrations of ir-BNP were found in the medulla-pons, striatum, and spinal cord. Medium concentration was noted in the hypothalamus. This distribution of ir-BNP in porcine brain was found to be different from that of ir-ANP simultaneously measured. Furthermore, BNP and BNP-32 were identified as two major forms of ir-BNP in porcine brain.

Amino Acid Sequence↗

PubMed1988

A new natriuretic peptide in porcine brain.

Atrial natriuretic peptide (ANP), a hormone secreted from mammalian atria, regulates the homoeostatic balance of body fluid and blood pressure. ANP-like immunoreactivity is also present in the brain, suggesting that the peptide functions as a neuropeptide. We report here identification in porcine brain of a novel peptide of 26 amino-acid residues, eliciting a pharmacological spectrum very similar to that of ANP, such as natriuretic-diuretic, hypotensive and chick rectum relaxant activities. The complete amino-acid sequence determined for the peptide is remarkably similar to but definitely distinct from the known sequence of ANP, indicating that the genes for the two are distinct. Thus, we have designated the peptide 'brain natriuretic peptide' (BNP). The occurrence of BNP with ANP in mammalian brain suggests the possibility that the physiological functions so far thought to be mediated by ANP may be regulated through a dual mechanism involving both ANP and BNP.

Amino Acid Sequence↗

PubMed1987

Identification of alpha atrial natriuretic peptide [4-28] and [5-28] in porcine brain.

Although atrial natriuretic peptide (ANP) has recently been verified to function as a neuropeptide in the central nervous system, its definite identification has not been done so far. We have isolated two ANP-related peptides from porcine brain by utilizing alpha-ANP specific radiommunoassay coupled with immunoaffinity chromatography and reverse phase HPLC. By structural analyses, these two peptides were determined to be alpha-ANP [4-28] and alpha-ANP [5-28]. They were found to elicit chick rectum relaxant activity comparable to alpha-ANP. These results indicate that proteolytic processing of ANP precursor in the central nervous system takes place in a manner different from that in heart and plasma, where gamma-ANP and alpha-ANP are known to be the main components of ANP, respectively.

Amino Acid Sequence↗

PubMed1987

Topographic localization of neuromedin U-like structures in the rat brain: an immunohistochemical study.

The distribution of neuromedin Us, uterus-stimulating and hypertensive peptides newly identified in porcine spinal cord, was examined in the rat brain by the indirect immunofluorescent method. Neuromedin U-like immunoreactive structures were found to be unevenly distributed in the neuronal system. Neuromedin U-like immunoreactive neurons were present in the cranial motor nuclei, reticular nuclei, nucleus vestibularis lateralis, trigeminal sensory nuclei, colliculus superior and inferior, lemniscus lateralis, nucleus pontis, nucleus ruber, zona incerta, substantia innominata, horizontal limb of the diagonal band and cerebral cortex. The immunoreactive fibres were found in the above areas, particularly near the labelled cells, forming a fibre plexus with various intensities of immunoreactivity. In addition, dense plexuses were also seen in the nucleus reticularis thalami, nucleus ventralis posteromedialis, nucleus ventralis posterolateralis, nucleus tegmentalis dorsalis and ventralis, vertical limb of the diagonal band, nucleus olivaris superior, and nucleus pontis. In the first six structures, no labelled neurons were present and in the remaining structures, a few scattered neurons were noted. This indicates that these fibres are probably of extrinsic origin.

Animals↗

PubMed1985

Neuromedin B-32 and B-30: two "big" neuromedin B identified in porcine brain and spinal cord.

In mammalian spinal cord, we have previously discovered "neuromedin B", whose structure is closely related to amphibian bombesin. By utilizing a specific radioimmunoassay for neuromedin B, we have isolated two novel "big" neuromedin B, designated neuromedin B-32 and B-30, from pig brain and spinal cord, both of which were identified as N-terminally extended forms of neuromedin B. The amino acid sequence of neuromedin B-32 was determined to be: Ala-Pro-Leu-Ser-Trp-Asp-Leu-Pro-Glu-Pro- Arg-Ser-Arg-Ala-Gly-Lys-Ile-Arg-Val-His-Pro-Arg-Gly-Asn-Leu-Trp-Ala- Thr-Gly-His-Phe-Met-NH2, while neuromedin B-30 was found to be an N-terminal two amino acids deleted form of neuromedin B-32. Isolation of a family comprising neuromedin B, B-30 and B-32 is indicative of their biosynthetic relationship.

Amino Acid Sequence↗

PubMed1985

Neuromedins: novel smooth-muscle stimulating peptides identified in porcine spinal cord.

Two novel peptides, neuromedin U-8 and U-25, eliciting a potent uterus stimulating activity, have been purified and identified in porcine spinal cord. Sequence analyses and syntheses revealed that neuromedin U-8 is a novel octapeptide with a C-terminal amide structure, while U-25 contains the U-8 sequence at its C-terminus, preceded by paired Arg residues, implicating their biosynthetic relationship. Their potent uterus stimulating activity and hypertensive effect, as well as their unique C-terminal amide structure are indicative of their specialized physiological function. In addition, by utilizing a specific radioimmunoassay for neuromedin B that is a bombesin-like peptide identified in porcine spinal cord, we have isolated two novel "big" neuromedin B, designated neuromedin B-32 and B-30, from pig brain and spinal cord, indicative of their biosynthetic relationship. Nine neuromedins (B, B-30, B-32, C, K, L, N, U-8 and U-25) thus far identified in porcine spinal cord as the smooth-muscle stimulating peptides, are classified into four families; B-(bombesin-like), K-(kassinine-like), N-(neurotensin-like) and U-groups.

Amino Acid Sequence↗