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Biomedical subjects

C Tanaka

Publications and source records attributed to C Tanaka.

At least 379 records · Page 21Linked to original sources
PubMed1983

Release of endogenous and labeled GABA from isolated guinea pig ileum.

The release of gamma-aminobutyric acid (GABA) was studied by comparing the properties of labeled GABA released from preloaded preparations to those of endogenous GABA released from the isolated guinea pig ileum. The spontaneous release of endogenous GABA was 4.46 +/- 0.10 pmol X min-1 X g wet wt-1, and the fractional rate of endogenous GABA release was much lower. The ratio of evoked to spontaneous release of endogenous GABA was high compared with that of labeled GABA. The electrical transmural stimulation-evoked release of labeled and endogenous GABA was inhibited by superfusion with tetrodotoxin and Ca2+-free Krebs-Ringer solution containing 1 mM ethyleneglycol-bis(beta-aminoethylether)-N,N'-tetraacetic acid. Thus the nature of the stimulation-evoked release of labeled GABA was similar to that of endogenous GABA. These results indicate that the released GABA is neuronal in origin and provide additional evidence for the presence of GABA-ergic neurons in the guinea pig ileum.

Animals↗
PubMed1983

Immunopharmacologic studies of D-penicillamine-L-cysteine disulfide.

Effects of D-penicillamine-L-cysteine disulfide (P-C) on some immunological parameters were examined in normal and immunity-impaired mice and rats. P-C enhanced the DNA synthesis in concanavalin A-stimulated mouse spleen cell cultures in vitro. In vivo, administration of P-C produced either enhancement or depression of plaque forming cell (PFC) response and delayed type hypersensitivity (DTH) to sheep red blood cells (SRBC) in low responder mice to SRBC, depending on the dose of P-C. P-C restored the impaired PFC response in hydrocortisone-pretreated mice. The enhancing effect of P-C was not shown in high responder mice to SRBC, but an inhibiting effect was observed. P-C inhibited the suppressor cell induction on PFC response in mice immunized with a supraoptimum dose of antigen. In adjuvant arthritic rats, P-C induced severe arthritis by eliminating the suppressor cells regulating this disease process. The relevance of these findings and mode of action of D-penicillamine in rheumatoid arthritis is discussed.

Animals↗
PubMed1983

Effect of partial hydrolyzates of casein and soybean protein on serum lipoproteins and fecal neutral steroids.

Effect of partial hydrolyzate of casein and soybean protein on serum lipoproteins and fecal neutral steroids in cholesterol-fed rats was studied. In rats fed partial hydrolyzate of casein, the levels of plasma and liver cholesterol, liver triglyceride and the ratio of serum beta/alpha lipoprotein had a tendency to decrease compared with those in rats fed intact protein. On the other hand, no difference was observed between soybean protein and partial hydrolyzate of soybean protein diet groups. The excretion of neutral steroids to feces and the amount of fecal coprostanol were increased in rats fed soybean protein and partial hydrolyzate of soybean protein.

Animals↗
PubMed1983

Effect of soybean protein on coprostanol production and cholesterol metabolism in cholesterol-fed rats.

The effect of soybean protein on coprostanol production and cholesterol metabolism was studied in cholesterol-fed rats. Plasma cholesterol was decreased in the soybean protein diet group compared to the casein diet group. Although coprostanol was produced more in rats fed soybean protein than in those fed casein, no difference was observed in the levels of total neutral steroids at any part of the intestine. The activity of microbial conversion from cholesterol to coprostanol was evidently high in rats fed soybean protein. The total amount of neutral steroids excreted in feces had a tendency to increase. These data seem to indicate that the increase of the unabsorbed soybean protein causes the increase of intestinal coprostanol production.

Animals↗
PubMed1983

Intraperiosteal osteoid osteoma. A case report.

A painful intraperiosteal osteoid osteoma of the femur occurred in a 36-year-old man. Histologically, the tumor was encapsulated by the periosteum. The pain was relieved by removal of the tumor. Thirty-four months after operation, there has been no recurrence. Osteoid osteoma in this location does not appear to have been reported previously.

Adult↗
PubMed1982

[Release of gamma-aminobutyric acid from cat colon].

The release of gamma-aminobutyric acid was confirmed in isolated cat colon loaded with tritiated gamma-aminobutyric acid. Thirty to 180 minutes after loading the spontaneous efflux of tritium appeared to fit a single exponential curve with an efflux rate coefficient of 0.002 per minute. Electrical stimulation produced frequency-dependent increases in the tritium efflux and in the contractions. Even 120 minutes later over 91 percent of the total radioactivity in the superfusates was attributable to tritiated gamma-aminobutyric acid. The acid release and the contractions induced by electrical transmural stimulation were inhibited by tetrodotoxin and by a calcium-free medium. Release of the acid was not significant during contractions elicited by nicotine and acetylcholine. These findings indicate that gamma-aminobutyric acid is released from the terminals of neurons in the myenteric plexus of the colon.

Acetylcholine↗
PubMed1982

Developmental and periovulatory changes of ovarian norepinephrine in the rat.

Norepinephrine (NE) and dopamine (DA) contained in the rat ovary were determined by high-performance liquid chromatography with electrochemical detection. Concentration of ovarian NE reached adult levels around 5 weeks of age, when the first ovulation occurs. During induction of ovulation, the ovarian NE contents increased slightly during the preovulatory phase, followed by a significant decrease in the postovulatory phase, whereas the turnover of ovarian NE decreased during the preovulatory phase. These results suggest that ovarian noradrenergic nerves were in a somewhat inactivated state during the preovulatory phase. Therefore, ovarian sympathetic nerves are considered to participate in mechanisms of the onset of puberty and ovulation.

Animals↗
PubMed1982

Presence of gamma-aminobutyric acid and glutamic acid decarboxylase in Auerbach's plexus of cat colon.

Regional distributions of endogenous gamma-aminobutyric acid (GABA) and ganglion cells in Auerbach's plexus were studied in the gastrointestinal tract of cats. GABA was determined by enzymatic and fluorometric assay. There was a positive correlation between the GABA content and the number of cells in this plexus. We analyzed the precise localization of GABA and glutamic acid-decarboxylase (GAD) in individual layers, mucosa, circular and longitudinal muscles and Auerbach's plexus, from freeze-dried sections of cat colon by the enzymatic cycling method. Both GABA contents and GAD activity in Auerbach's plexus were highest in all 4 layers. Thus, the possibility that GABA is synthesized and localized within Auerbach's plexus has to be considered.

Animals↗
PubMed1982

Asplenia and polysplenia syndrome.

This report described the morphological characteristics of seven cases of asplenia syndrome and three of polysplenia syndrome. Each syndrome has been characterized by a tendency for symmetric development of normally asymmetric organs, with varying degrees of cardiovascular anomalies. These latter anomalies are usually present in asplenia syndrome to a greater extent than in polysplenia syndrome. While, as observed in our material, the conotruncal anomalies were present more commonly in cases with asplenia, and absence of inferior vena cava with azygos continuation was seen specifically in all the cases with polysplenia. This evidence implied the presence of some pathogenetic distinction between the two syndromes.

Abnormalities, Multiple↗
PubMed1982

Increase of anti-ulcerogenic activity by reduction and alkylation of disulfide bonds of a globulin fraction from bovine serum.

Bovine serum was subjected to ammonium sulfate fractionation, and subsequently chromatographed on DEAE-cellulose column to obtain a globulin protein having a weak anti-ulcerogenic activity, Fr.II-A. Agar immunoelectrophoresis and immunodiffusion using rabbit antiserum against bovine IgG revealed that Fr.II-A from bovine serum shared antigenic determinant with bovine IgG. Furthermore, Fr.II-A showed a single band on polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate. By reducing and alkylating the disulfide bonds by 2-mercaptoethanol and iodoacetic acid, Fr.II-A was separated into two subfragments in the same manner as in the case of immunoglobulin to produce Fr.L (molecular weight; 24000) and Fr.H (molecular weight; 50000). Fr.L showed anti-ulcerogenic activity up to about ten times greater than that of original Fr.II-A, but in the case of Fr.H, the activity increased approximately several times. Fr.L showed significant activity in preventing ulcer formation and gastric juice secretion in pylorus-ligated rats, and was also effective in reducing index of the phenylbutazone-induced ulcer.

Alkylation↗
PubMed1982

Multivariate analysis using a linear discriminant function for predicting the prognosis of congestive heart failure.

Some of cases of congestive heart failure (CHF) are intractable or refractory and respond poorly to conventional treatment. We have examined factors which may influence the clinical course and prognosis. The subjects were 114 hospitalized patients with CHF. Of these, 77 had a good response to treatment and were classified as the curative group (Group C) while the remaining 37 who were difficult to treat, including those with poor prognosis, were designated the refractory group (Group R). Of the various clinical background factors including the findings of laboratory and other examinations, the following 8 variables made a significant contribution to differentiation between the 2 groups: 1) heart rate (X1), 2) hemoglobin content (X2), 3) serum K (X3), 4) serum total protein (X4), 5) A/G (X5), 6) BUN (X6), 7) grade of hepatomegaly (X7), and 8) number of previous CHF episodes (X8). The linear discriminant function represented by the following equation using these 8 variables showed an excellent result in differentiating the 2 groups. Y = - 9.64 - 0.0686X1 + 0.345X2 + 1.351X3 + 1.513X4 + + 1.988X5 - 0.0876X6 - 0.792X7 - 0.737X8. When Y value is over 0, Group C is judged. When Y value is under 0, group R is judged. We concluded that the discriminant equation covering these 8 factors is a useful means of predicting the prognosis in CHF and the response to treatment.

Adult↗