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K Kurihara

Publications and source records attributed to K Kurihara.

At least 271 records · Page 15Linked to original sources
PubMed1985

Evidence for non-receptor odor discrimination using neuroblastoma cells as a model for olfactory cells.

The mouse neuroblastoma cell (N-18 clone), which is independent of an olfactory cell, was depolarized by 20 odorants examined, suggesting that specific proteins are not required for reception of odorants. The mechanism of non-receptor-mediated odor discrimination was examined using the N-18 cell. Changes in the membrane fluidity of the cell induced by adsorption of odorants were measured with various fluorescence probes, which monitor the fluidity at the different depth and in the different phase of the membrane. The profiles of the membrane fluidity changes monitored with these dyes were different from one species of odorants to another, suggesting that odorants having different odors are adsorbed at different sites in the membranes. The alteration of the lipid composition of the cell membrane brought about by exogenous application of stearic acid and cholesterol led to modification of the responses (magnitude of depolarization) to various odorants. The extent and direction (increase or decrease) of changes in the responses greatly varied among species of odorants. The following mechanism on odor discrimination was proposed. A membrane composition of each olfactory cell is postulated to be different from cell to cell. Different combinations of lipids and proteins in the membranes provide different adsorption sites for odorants. Relative amounts of the membrane potential changes in many olfactory cells in response to an odorant are characteristic of the species of the odorant. The response profiles at the cell level determine the quality of the odor.

Animals↗
PubMed1985

Heterogeneity in the metabolism of the arachidonoyl molecular species of glycerophospholipids of rabbit alveolar macrophages. The interrelationship between metabolic activities and chemical structures of the arachidonoyl molecular species.

The relative incorporation of [3H]arachidonic acid (20:4) into individual molecular species containing 20:4 at the 2 position (18:1-20:4, 16:0-20:4 and 18:0-20:4 species) of diacyl and ether-linked glycerophosphocholine, glycerophosphoethanolamine and glycerophosphoinositol of rabbit alveolar macrophages has been measured by reversed-phase high-performance liquid chromatography (HPLC). The rate of incorporation of [3H]20:4 into the molecular species of glycerophospholipids was greatly influenced by their structures. The reversed-phase HPLC analysis allowed elucidation of the influence of structural differences, such as the nature of the polar head group, the fatty chain at the 1 position and the chemical form of the bond of the fatty chain attached at the 1 position on the uptake of [3H]20:4 by comparison of the specific radioactivities of arachidonoyl molecular species having the same structures, except that one of the three kinds of moiety was different. The specific radioactivities of the molecular species containing choline head groups were significantly higher than those containing ethanolamine and inositol moieties. The specific radioactivities of diacyl molecular species were considerably higher than those of ether-linked molecular species. The nature of the fatty chain attached at the 1 position also influenced the uptake of [3H]20:4 into glycerophospholipids. The arachidonoyl molecular species containing 18:1 at the 1 position were preferentially labelled with [3H]20:4 as compared to the corresponding 16:0-20:4 and 18:0-20:4 species either of diacyl or ether-linked glycerophospholipids. The present results suggest that the acyltransferase involved in the incorporation of 20:4 into glycerophospholipids has selectivity for the structures of glycerophospholipids and the order of selectivity of this enzyme for the arachidonoyl molecular species, deduced in the present experiments, was as follows: choline head group greater than ethanolamine and inositol groups, acyl bond greater than ether and vinyl ether bonds, 18:1 fatty chain greater than 16:0 and 18:0 fatty chains at the 1 position. Comparison of the metabolic activities of all major arachidonoyl molecular species of glycerophospholipids having a single structure is reported here for the first time.

Animals↗
PubMed1985

Neuroblastoma cell as a model for a taste cell: mechanism of depolarization in response to various bitter substances.

The mouse neuroblastoma cell (N-18 clone) was used as a model for a taste cell. The N-18 cell was found to be reversibly depolarized by various bitter substances. The minimum concentrations of bitter substances which induced depolarization (threshold concentration) varied greatly with the type of the substance. There was a good correlation between the threshold concentrations for various bitter substances in the N-18 cell and those in the human taste responses. The input membrane resistance was little changed during the depolarization induced by the bitter substances. Replacement of Na+ and Cl- with impermeable ions had practically no effect on the depolarization response to the bitter substances and reduction of calcium concentration from 1.8 to 0.2 mM led to a slight increase in the responses. It was suggested that the depolarization of the N-18 cell by bitter substances mainly stems from changes in the phase-boundary potential at the outer surface of the cell.

Animals↗
PubMed1985

Norepinephrine as a possible transmitter involved in synaptic transmission in frog taste organs and Ca dependence of its release.

In order to explore the role of catecholamine and Ca2+ in the synaptic transmission from taste cells to sensory nerve terminals, the effects of various agents added to an artificial solution perfusing the lingual artery on the frog taste nerve responses were examined. The injection of reserpine or guanetidine, which are catecholamine-depleting agents, led to a great reduction of the frog taste nerve responses. The addition of catecholamines to the perfusing solution did not practically enhance the spontaneous impulse discharges, but did recover the response to all the taste stimuli examined. Norepinephrine was most effective and is the most likely candidate for the transmitter. The enhancement of the responses by norepinephrine was suppressed by desipramine, cocaine, or imipramine, which suggests that the enhancement was brought about by incorporation of norepinephrine into taste cells. In a previous paper (Nagahama, S., Y. Kobatake, and K. Kurihara, 1982. J. Gen. Physiol. 80:785), we showed that the responses to the stimuli of one group depended on Ca2+, cGMP, and cAMP added to the perfusing solution and those to the stimuli of another group did not depend on these agents. After the injection or addition of reserpine to the lingual artery, which probably modified injection or addition of reserpine to the lingual artery, which probably modified the permeability of the artery, the responses to the stimuli of the latter group also came to exhibit dependences on these agents, which indicates that the responses to all the taste stimuli have dependences on Ca2+, cGMP, and cAMP.

Animals↗
PubMed1985

The acute effects of cigarette smoke exposure on experimental skin flaps.

Random vascular patterned caudally based McFarlane-type skin flaps were elevated in groups of Fischer 344 rats. Groups of rats were then acutely exposed on an intermittent basis to smoke generated from well-characterized research filter cigarettes. Previously developed smoke inhalation exposure protocols were employed using a Maddox-ORNL inhalation exposure system. Rats that continued smoke exposure following surgery showed a significantly greater mean percent area of flap necrosis compared with sham-exposed groups or control groups not exposed. The possible pathogenesis of this observation as well as considerations and correlations with chronic human smokers are discussed. Increased risks of flap necrosis by smoking in the perioperative period are suggested by this study.

Animals↗
PubMed1985

The pathological significance of Langerhans cells in oral cancer.

The functional role of Langerhans cells (LCs) in oral cancer was studied, based on a quantitative analysis of LCs in squamous cell carcinomas arising from the tongue. LCs were identified by their positiveness for S100-protein and other cytological characters based on PAP method. LCs increased in number in the cancer region and showed an intimate relationship with lymphocytes in terms of their number and distribution. Moreover, in those cases with many LCs, clusters consisting of LCs and lymphocytes were often found to combine into "hydropic degeneration-like" lesions as seen in allergic disease such as dermal lichen planus. These findings, as well as the review of literature, suggested some immunological role of LCs in oral carcinoma.

Carcinoma, Squamous Cell↗
PubMed1985

[Morphological study of carcinoma of the gallbladder: its differences between calculous and acalculous carcinoma].

The most characteristic phenomenon in patients with carcinoma of the gallbladder is frequent coexistence of gallstones. In this study, morphological differences of carcinoma of the gallbladder in between calculous and acalculous cases is investigated. This study involved fifty-three cases (eleven early carcinoma and forty-two advanced) that had been surgically treated at the Hamamatsu Medical Center Hospital during the past ten years. Nine of 11 early carcinomas were calculous and two, acalculous. All calculous carcinomas showed grossly superficial type and two acalculous, polypoid type. All of them were histologically differentiated adenocarcinoma. In advanced carcinoma, thirty-one of 42 cases were calculous and eleven, acalculous. Fifteen of 31 calculous cases showed polypoid type and sixteen, diffuse infiltrative type. In all cases with the latter type, the cystic duct was completely obstructed by impacted gallstones. All calculous carcinomas were histologically belonged to differentiated adenocarcinoma, mucinous carcinoma or adenosquamous carcinoma. On the other hand, six of 11 acalculous carcinomas revealed grossly polypoid type, and histologically differentiated adenocarcinoma or mucinous carcinoma. The remaining five were of diffuse infiltrative type, and of poorly-differentiated adenocarcinoma or signet-ring cell carcinoma. From these data, it may be highly suggestive that differentiated adenocarcinoma or adenosquamous carcinoma of histologic type irrespective of it's gross type is characteristic of calculous carcinoma, and poorly-differentiated adenocarcinoma or signet-ring cell carcinoma possessing primary diffuse infiltrative growth, of acalculous. The majority of the superficial type in early carcinoma and the diffuse infiltrative type in advanced are considered as a secondary modified gross appearance by direct or indirect effects of coexistent gallstones onto the main tumor.

Adenocarcinoma↗
PubMed1984

Multiple receptor types for amino acids in the carp olfactory cells revealed by quantitative cross-adaptation method.

A quantitative method of cross-adaptation was developed to explore the difference in the receptor sites for various amino acids in the carp olfactory receptors. The olfactory responses were measured by recording the stimulant-induced waves from the olfactory bulb. Cross-adaptation was carried out by varying concentrations of amino acids in a wide range. Typical examples of the results obtained are as follows. The response to Thr after Ser was decreased with increasing concentration of Ser applied first and reached the spontaneous level, while that to Thr after Glu was decreased to 77% of the level of the original response with increasing Glu concentration and stayed this constant level with a further increase in Glu concentration. Application of the amino acids in the reverse order gave essentially similar results. Such types of experiments were carried out between various pairs of amino acids. The results obtained suggested that amino acids of very close species (e.g. Thr and Ser, Asp and Glu, Tyr and Phe) stimulate the same respective receptor sites and that amino acids of most other pairs stimulate more or less different receptor sites, although there exist the receptor sites stimulated commonly by both amino acids of one pair. It was concluded that the carp olfactory cells have many different receptor sites stimulated only by one species of amino acid and its close analogues.

Animals↗
PubMed1984

Contribution of surface potential to resting potential in mouse neuroblastoma cells: estimation with fluorescent dyes and from shift of threshold potential for Ca-spike.

The contribution of the changes in the diffuse double layer potential (surface potential) to the resting membrane potential of the mouse neuroblastoma (N-18 clone) was estimated with the use of fluorescent dyes and from the shift of the threshold potential of the Ca-spike. The membrane potential monitored by Rhodamine 6G was unchanged with variations of external K+ concentration [( K+]o) below about 10 mM, and changed linearly with log [K+]o above this concentration, similar to the changes observed with a microelectrode. This result indicates that the independence of the membrane potential of [K+]o at low [K+]o is not brought about by the artifacts caused by insertion of a microelectrode into the cell. The changes in the surface potential in response to various polyvalent cations (Mg2+, Ca2+, Mn2+, Cd2+ and La3+) were monitored by the fluorescence of ANS. The behavior of the surface potential thus observed was closely correlated with that of the membrane potential for the respective polyvalent cations. The surface potential changes in response to increase in [Ca2+]o from 1.8 to 100 mM and in [Mg2+]o from 0.8 to 100 mM were 88% and 85% in magnitude compared with the corresponding changes in the membrane potential, respectively. The effect of variation of [Ca2+]o on the threshold potential of the Ca-spike was compared with that of [Ca2+]o on the resting membrane potential. The magnitude of the surface potential change determined by the shift of the threshold potential was comparable to the magnitude of the membrane potential change. The results in the present study suggest that the surface potential change produced at the membrane surface of N-18 cells is detected as a transmembrane potential change without a large reduction in magnitude.

Anilino Naphthalenesulfonates↗
PubMed1984

Neuroblastoma cell as model for olfactory cell: mechanism of depolarization in response to various odorants.

The mouse neuroblastoma cell (N-18 clone) was used as a model for an olfactory cell. The N-18 cell was found to be depolarized reversibly by various species of odorants. The minimum concentrations of odorants which induced depolarization (threshold concentration) varied greatly with the species of odorants. There was a good correlation between the order of the threshold concentrations for various odorants in the N-18 cell and that in the frog olfactory responses. Replacement of Na+ and Cl- with impermeable ions or reduction of calcium concentration from 1.8 mM to 0.1 mM had practically no effect on the magnitude of the depolarization response to odorants. The input membrane resistance was little changed during the depolarization induced by various odorants. No reversal potential was observed when the cell was depolarized by n-amyl acetate or vanillin. It is suggested that the depolarization of N-18 cell by odorants is induced by changes in the phase-boundary potential at the outer surface of the cell.

Animals↗
PubMed1984

Enhancement of taste responses to acids by calcium ions.

The frog taste nerve responses to HCl and acetic acids were greatly enhanced by increasing calcium concentration in a solution to which the tongue had adapted when the lingual artery was perfused with Ringer solution. Enhancement was not seen in the responses to other taste stimuli.

Acids↗
PubMed1984

Frontalis suspension for blepharoptosis using palmaris longus tendon.

In treatment of moderate to severe blepharoptosis in the Oriental, an excellent result can be obtained by frontalis suspension using free palmaris longus tendons. Postoperative functional training is unnecessary. Children of 5 or 6 with congenital upper eyelid ptosis are favorable candidates for correction by this method. In traumatic cases, the operation may be performed about six months after injury.

Adult↗
PubMed1984

Nerve staining with leucomethylene blue: an experimental study.

Identification and preservation of the facial nerve during extirpative and reconstructive surgery represents a challenge even for the experienced surgeon. We present an experimental intraoperative technique for staining the facial nerve and its branches that is safe, accurate, and inexpensive. Leucomethylene blue is injected into the precise region of the facial nerve. Staining of the surrounding tissues is efficiently reduced by irrigation with ascorbic acid solution, leaving only the facial nerve stained. This technique has been encouraging in rabbits, and with additional experience, we anticipate its use for intraoperative staining of the facial nerve in humans.

Animals↗
PubMed1984

Russell body-like inclusions in oral B-lymphomas.

Two cases of oral B-lymphomas with numerous Russell body-like inclusions are described. One occurred primarily in the hard palate of a 59-year-old female with Sjögren's syndrome, and was diagnosed as lymphoplasmacytoid immunocytoma by Kiel's classification. The other occurred secondarily in the buccal mucosa of a 44-year-old female whose first affected site was orbital soft tissues, and was diagnosed as extramedullary plasmacytoma. The diagnostic problems and the nature of the Russell body-like inclusions are discussed based on the immunoperoxidase (PAP) method and electron microscopic study. The first patient is well without recurrence 19 months after surgery, while the second patient developed extramedullary plasmacytoma in the abdomen 5 months after surgery for the buccal plasmacytoma.

Adenoma, Pleomorphic↗