Biomedical subjects

K Kishida

Publications and source records attributed to K Kishida.

148 records · Page 9Linked to original sources

PubMed1967

Amino acids and the spikes from the retinal ganglion cells.

The effects of amino acids or mixtures of amino acids on the spike discharges from the optic ganglion cells were studied. Mixtures of amino acids have different effects than single amino acids. Proper composition of excitatory and inhibitory amino acids can enhance only the light-induced spikes without giving rise to any spontaneous discharges. It is implied that amino acids may play an important role in the regulation of the general sensitivity of cells in the central nervous system.

Alanine↗

PubMedDate not supplied

Sodium and chloride transport across the isolated rabbit ciliary body.

Unidirectional Na+ and Cl- fluxes were determined in the isolated rabbit ciliary body under short-circuited conditions. A statistically significant net Cl- flux towards aqueous was detected in the standard bathing solution (HCO3- = 115 mM), but no net Na+ flux was demonstrated in this solution. The net Cl- flux exceeded the short-circuit current, suggesting the existence of a net flux of other ion(s). In a bathing solution containing 5 mM HCO3-, the net Cl- flux was abolished, suggesting that HCO3- in the bathing solution enhances the net Cl- flux.

Action Potentials↗

PubMedDate not supplied

The influence of tryptophan and its metabolites upon rabbit lens electrolyte balance.

The effect of tryptophan and three major metabolites of tryptophan on the rabbit lens electrolyte balance was examined. Even at 3 x 10(-3) M tryptophan, tryptamine and xanthurenic acid had no effect on lens sodium, potassium and calcium content after a 20 hr incubation. Small but significant changes in lens sodium and potassium content were induced by 20 hr incubation in 2 x 10(-3) M 3-hydroxy-DL-kynurenine and 10(-3) M hydroxyanthranilic acid. Lens Na, K-ATPase activity was unaffected by 3 x 10(-3) M tryptophan. Tryptamine reduced, to a small extent, Na,K-ATPase activity at 3 x 10(-3) M, but was without effect at 10(-3) M. 3-hydroxy-DL-kynurenine (2 x 10(-3) M) and 3-hydroxyanthranilic acid (10(-3) M) inhibited Na,K-ATPase activity by 27% and 30% respectively. Only 3-hydroxy-DL-kynurenine had a demonstrable effect on 86Rb uptake. It is concluded that, in contrast to findings in the amphibian lens, metabolites of tryptophan have minimal or no detrimental effects upon rabbit lens electrolyte balance under the in vitro conditions of these experiments. However, this does not rule out a long term effect of these compounds should they accumulate in the lens.

Adenosine Triphosphatases↗

PubMedDate not supplied

Immunological study of childhood acute ITP at onset.

We attempted to search for any specific change in the immune system during the onset of childhood acute immune thrombocytopenic purpura (ITP) in order to clarify the pathophysiology of acute ITP by examining the lymphocyte subset, lymphocyte blastogenic response, serum complements, and immunoglobulins in 18 patients with childhood acute ITP and 18 controls (control values after normalization). At the onset of acute ITP, the levels of serum complements and IgG and IgA were found to be within the normal ranges, but serum IgM levels were greater than 200 mg/dL in six cases among 18 patients. Lymphocyte blastogenic response to phytohemagglutinin (PHA) and concanavalin A (ConA) was depressed in patients relative to controls (PHA: p less than 0.05, ConA: p less than 0.01). Lymphocyte blastogenic response to pokewood mitogen (PWM) was lower than that of the control, but no statistical significance was observed. There was no difference in the proportion of CD3, CD4, CD8, SmIg, SmIgG, SmIgM, SmIgA, and SmIgD. The CD4/CD8 ratio was not different from that of controls. The proportion of CD38 was higher than that of control, but no significant difference from the control was observed. Increase in the serum IgM level and proportion of CD38 and depressed lymphocyte blastogenic response may be the influence of preceding infection. It has been reported that the CD4/CD8 ratio is depressed due to an increase in the CD8 level in acute and convalescent phases of viral infection. However, the proportion of CD8 was not necessarily increased in our patient in whom preceding infection was obvious. The immunological status of the patients with acute ITP at onset differs from that after infection.

ADP-ribosyl Cyclase↗