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Biomedical subjects

Y Onishi

Publications and source records attributed to Y Onishi.

At least 127 records · Page 7Linked to original sources

Substance P-evoked release of GABA from isolated spinal cord of the newborn rat.

Isolated spinal cords of newborn rats were perfused with artificial cerebrospinal fluid and the effects of substance P and its analogs on the release of endogenous GABA were examined. Application of substance P evoked a dose-dependent release of GABA from spinal cords. The threshold concentration of substance P for induction of a significant increase in the GABA release was 3 microM. The substance P-evoked GABA release was neither blocked by removal of Ca2+ from perfusion medium nor by tetrodotoxin. In contrast, the GABA release evoked by high K+ (90 mM) was abolished in Ca(2+)-free medium, and the GABA release evoked by veratridine (5 microM) was suppressed by tetrodotoxin (1 microM). A GABA uptake inhibitor, cis-4-hydroxynipecotic acid, markedly augmented the GABA release induced by high K+, but not that induced by substance P or veratridine. These results suggest the possibility that a carrier-mediated mechanism might be involved in the GABA release induced by substance P, as well as by veratridine, in the newborn rat spinal cord. Two N-terminal fragments of substance P, substance P free acid and substance P1-10 amide, as well as [D-Arg1,D-Trp7,9,Leu11]substance P (spantide), evoked an increase in the GABA release, whereas substance P1-6, and a C-terminal fragment, substance P5-11 were inactive. Somatostatin and compound 48/80 also evoked a GABA release, which was independent of external Ca2+ and resistant to tetrodotoxin. [D-Pro4,D-Trp7,9,10]substance P4-11 (10-15 microM) inhibited the GABA release evoked by substance P, somatostatin and compound 48/80.(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acid Sequence↗

Substance P-evoked release of acetylcholine from isolated spinal cord of the newborn rat.

Isolated spinal cords of newborn rats were perfused with artificial cerebrospinal fluid and the release of endogenous acetylcholine was measured using high-performance liquid chromatography with an electrochemical detection system. Application of high-K+ (90 mM) medium evoked about an eight-fold increase in the acetylcholine release, and the K(+)-evoked release was Ca2+ dependent. Veratridine (20 microM) also evoked about a four-fold increase in the acetylcholine release, and this increase was suppressed by 0.2 microM tetrodotoxin. Application of substance P at 0.3-3 microM evoked a concentration-dependent release of acetylcholine. The substance P-evoked acetylcholine release was Ca2+ dependent and abolished by tetrodotoxin. Neurokinin A, neurokinin B, acetyl-Arg6-septide and senktide (3 microM each) also evoked a release of acetylcholine. Electrophysiological experiments using isolated spinal cords of newborn rats showed that bath application of substance P induced a depolarization of motoneurons, which was enhanced by edrophonium. This enhancement of substance P-induced depolarization by edrophonium disappeared in a low-Ca2+ medium or in the presence of atropine and dihydro-beta-erythroidine. In the presence of edrophonium and dihydro-beta-erythroidine, substance P induced an inhibition of monosynaptic reflex, and this inhibition was abolished by atropine. These results suggest that substance P and other tachykinins induce a release of acetylcholine from the newborn rat spinal cord by exciting cholinergic neurons.

Acetylcholine↗

Unusual clinical presentation of malignant histiocytosis in a 70-year-old woman.

A 70-year-old woman was admitted for evaluation of hepatosplenomegaly, fever and elevated serum LDH levels. A biopsy specimen of the liver revealed histiocytic proliferation at the portal triad, and a mild degree of hepatitis. A bone marrow biopsy specimen showed proliferation of histiocytes with minimal immaturity and atypism, and haemophagocytosis by the proliferated histiocytes. Fever, hepatosplenomegaly and elevation of LDH levels all disappeared spontaneously, and presumptive diagnosis of benign reticulosis with haemophagocytosis was made. One year later, fever, hepatosplenomegaly and elevation of LDH levels redeveloped, and the liver and bone marrow biopsy specimen showed proliferation of unequivocally malignant histiocytes. The patient died as a result of disseminated intravascular coagulation with shock 20 d later. We concluded that, in this case, malignant histiocytosis first presented as benign haemophagocytic reticulosis and, 1 year later, there was a typical malignant presentation.

Aged↗

delta 4-3-Oxosteroid 5 beta-reductase. Structure and function.

delta 4-3-Oxosteroid 5 beta-reductase catalysing reduction of delta 4-3-oxosteroids to give A/B cis-conformation was intraperitoneally injected into BALB/c strain mice with Ribi adjuvant. Monoclonal antibody specific for this enzyme was prepared from their spleen cells. Using this monoclonal antibody as a probe the enzyme was further purified using reversed phase liquid chromatography to determine amino-acid sequence protein-chemically. Attempts to determine the N-terminal amino acid failed, indicating that the N-terminal amino acid is blocked. The protein was therefore subjected to digestion with lysyl endopeptidase after alkylating with iodoacetate. The peptides thus formed were isolated and purified by reversed-phase high-performance liquid chromatography and their amino-acid sequences were determined. Using antibodies and oligonucleotides as probes a cDNA which contained a 978 bp long open reading frame encoding 326 amino-acid residues (Mr 37376) was isolated from rat liver cDNA libraries and the entire sequence of the protein was deciphered from its nucleotide sequence. The COS cells transfected with this cDNA revealed a versatile activity to reduce varied kinds of delta 4-3-oxosteroids, i.e. 7 alpha-hydroxy-4-cholesten-3-one, androstenedione and cortisone as postulated by Okuda and Okuda (1984, J. Biol. Chem. 259, 7519-7524) and Furuebisu et al. (1987, Biochim. Biophys. Acta 912, 110-114. With a newly established immunoblotting assay method several tissues and organs were surveyed and it was found that the enzyme exists only in the liver and there is an apparent difference between sexes as to the content of this enzyme. However, there was little if any difference in the amount of mRNAs between both sexes, which may indicates that the sexual difference of rat liver cytosol 5 beta-reductase is due to a posttranslational modification and/or degradation.

Amino Acid Sequence↗

[Evaluation of antiemetic effect of clonazepam, metoclopramide, dexamethasone and diphenhydramine for prevention of cisplatin-induced vomiting].

In prospective alternative crossover test, we confirmed significant superiority of a three-drug combination of clonazepam (C) lorazepam (L) and dexamethasone (D) to (L) and (D) to control vomiting induced by 50 mg/m CDDP containing chemotherapy for gynecological malignancies (p less than 0.001). Vomiting frequency in initial 24 hours was 2.28 +/- 2.21 and 6.00 +/- 3.80 times a day respectively. According to this result, clonazepam, dexamethasone, metoclopramide and diphenhydramine (B) were used as a second regimen to control the vomiting in 80 mg/m CDDP containing chemotherapy for ovarian cancer patients. Clonazepam (2 mg 2 times p.o. -4 and 0 hrs before CDDP drip), dexamethasone (8 mg 5 times iv from -3 hrs each 3 hrs), metoclopramide (2.5 mg/kg iv loading from -2 hrs with 0.4 mg/kg/hr continuous infusion for 9 hrs) and diphenhydramine (30 mg/body 2 times im -2.6 hrs) were chosen to control CDDP-induced nausea and vomiting. These four drugs (C+L+D+B) prominently inhibited the chemo-induced vomiting up to 0.44 +/- 1.50 times a day, and 87.5% of courses was completely satisfactory.

Adult↗

[Clinical effects of terodiline hydrochloride for urinary frequency and sense of residual urine].

The clinical effects of terodiline hydrochloride were evaluated in forty-four patients with urinary frequency and/or sense of residual urine. After a four-week treatment with 24 mg terodiline hydrochloride once daily, subjective symptoms were improved and micturition frequency was decreased significantly. Slight dysuria was reported as a side effect only in one patient. Terodiline hydrochloride is considered to be superiorly effective and safe for the treatment of urinary frequency and sense of residual urine.

Adult↗

Concentrations of thyroxine-binding globulin in sera and peritoneal dialysates in patients on chronic peritoneal ambulatory dialysis.

Losses in thyroxine-binding globulin (TBG) in peritoneal dialysate and thyroid function were evaluated in patients undergoing continuous ambulatory peritoneal dialysis (CAPD), in comparison to patients on hemodialysis (HD) without TBG loss in the dialysate. The TBG concentration in the peritoneal dialysate was 0.26 +/- 0.09 microgram/ml (mean +/- SD, n = 24), with a daily loss of 2.47 +/- 0.94 mg. The serum TBG level in CAPD patients was 21.0 +/- 4.71 micrograms/ml (n = 24), which was not significantly different from that in HD patients (20.0 +/- 5.72 micrograms/ml, n = 24) or in healthy Japanese subjects. The serum TBG level correlated positively with the TBG loss and TBG level in the peritoneal dialysate (p less than 0.001). The serum T4 level in CAPD patients (4.93 +/- 1.38 microgram/dl, n = 24) was significantly greater than in HD patients (4.08 +/- 1.30 microgram/dl, n = 24, p less than 0.05).

Adult↗

ABO (H) blood group antigens and carcinoembryonic antigens as indicators of malignant potential in patients with transitional cell carcinoma of the bladder.

Immunoperoxidase methods were used to study ABO(H) blood group antigens and carcinoembryonic antigens in patients with transitional cell carcinoma of the bladder. In our study absence of blood group antigens in cancer tissues was not found to be correlated with histologic grade, stage and survival rate in patients with bladder carcinoma, while it was correlated with subsequent intravesical recurrences. In contrast, the presence of carcinoembryonic antigens in cancer tissues was correlated well with histologic grade, stage and survival rate. Our results suggest that immunoperoxidase detection of blood group antigens could not predict poor survival. In contrast, immunoperoxidase detection of carcinoembryonic antigens is of prognostic value in patients with transitional cell carcinoma of the bladder.

ABO Blood-Group System↗