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Ono S, Sasabuchi Y, Yamana H, Yokota I, Okada A, Matsui H, Itai S, Yonenaga K, Tonosaki K, Watanabe R, Ono Y, Yasunaga H, Hoshi K. Weight loss and functional decline in older Japanese people: A cohort study using large-scale claims data. Arch Gerontol Geriatr 2024; 120:105354. [PMID: 38309105 DOI: 10.1016/j.archger.2024.105354] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2023] [Revised: 01/19/2024] [Accepted: 01/28/2024] [Indexed: 02/05/2024]
Abstract
BACKGROUND The association between weight loss and subsequent functional decline is uncertain. The study aims to elucidate the association between weight loss over a year and subsequent functional decline requiring assistance in performing their activities of daily living in older individuals. METHODS The study used data from the publicly funded Long-Term Care Insurance service in Japan, which provides coverage for long-term care services for individuals unable to perform activities of daily living due to physical or cognitive impairment. The study enrolled people born in or before 1949, who underwent health checkups in both 2014 and 2015. The participants were followed from 2015 to the worsening of functional decline requiring long-term care services, death, or February 28, 2019, whichever occurred first. The risk of subsequent functional decline in each weight loss category was estimated using a Cox regression model adjusted for age, sex, baseline body mass index, smoking, and Charlson comorbidity index. RESULTS We identified 67,452 eligible individuals from the database. The median follow-up period was 1,284 days. The hazard ratios (95 % confidence interval) of functional decline for -1 %, -2 %, -3 %, -4 %, and ≤-5% weight change compared to 0 % weight change were 1.17 (1.03-1.32), 1.26 (1.11-1.43), 1.29 (1.12-1.49), 1.61 (1.39-1.87), and 1.79 (1.58-1.99), respectively. CONCLUSIONS AND IMPLICATIONS Older people with weight loss of 1 % or more were at risk of functional decline. Close weight monitoring may serve as an easy and inexpensive means of identifying older individuals at risk of functional decline.
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Affiliation(s)
- Sachiko Ono
- Department of Eat-loss Medicine, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-Ku, Tokyo 113-8655, Japan.
| | - Yusuke Sasabuchi
- Department of Real World Evidence, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Hayato Yamana
- Data Science Center, Jichi Medical University, Tochigi, Japan
| | - Isao Yokota
- Department of Biostatistics, Graduate School of Medicine, Hokkaido University, Hokkaido, Japan
| | - Akira Okada
- Department of Prevention of Diabetes and Lifestyle-Related Diseases, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Hiroki Matsui
- Data Science Center, Jichi Medical University, Tochigi, Japan; Department of Clinical Epidemiology and Health Economics, School of Public Health, The University of Tokyo, Tokyo, Japan
| | - Shunsuke Itai
- Department of Eat-loss Medicine, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-Ku, Tokyo 113-8655, Japan
| | - Kazumichi Yonenaga
- Department of Eat-loss Medicine, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-Ku, Tokyo 113-8655, Japan
| | - Kanata Tonosaki
- Department of Eat-loss Medicine, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-Ku, Tokyo 113-8655, Japan
| | - Rinji Watanabe
- Department of Eat-loss Medicine, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-Ku, Tokyo 113-8655, Japan
| | - Yosuke Ono
- Department of General Medicine, National Defense Medical College, 3-2 Namiki, Tokorozawa, Saitama 359-8513, Japan
| | - Hideo Yasunaga
- Data Science Center, Jichi Medical University, Tochigi, Japan; Department of Clinical Epidemiology and Health Economics, School of Public Health, The University of Tokyo, Tokyo, Japan
| | - Kazuto Hoshi
- Department of Eat-loss Medicine, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-Ku, Tokyo 113-8655, Japan
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Tonosaki K, Yonenaga K, Ono S, Itai S, Oyama S, Mizuno T, Watanabe R, Hoshi K. Saturation of Percutaneous Oxygen Decreases with Meal Consumption in Patients with Acute Pneumonia. Tokai J Exp Clin Med 2023; 48:123-127. [PMID: 37981847] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Accepted: 08/16/2023] [Indexed: 11/21/2023]
Abstract
OBJECTIVE This study aimed to investigate how respiratory status may be affected during meal consumption in patients with acute pneumonia, mainly aspiration pneumonia, using percutaneous oxygen saturation (SpO2) and pulse rate (PR) measurements. METHODS We recruited 44 inpatients at the Towada City Hospital and divided them into 'pneumonia' and 'control' groups. Generalized linear mixed effects model was used for analysis. The pneumonia group comprised 22 patients (mean age 81.2 ± 7.0 years, body mass index [BMI] 21.1 ± 4.0 kg/m2) with 1-3 points A-DROP scores. The control group comprised 22 patients (mean age 80.5 ± 4.9 years, BMI 20.9 ± 2.9 kg/m2) with no obvious respiratory diseases. SpO2 and PR were measured 30 min before, during, and 30 min after meals. RESULTS SpO2 was significantly lower during meals in the pneumonia group (-1.60%; 95% confidence interval = -2.76 to -0.44). There were no significant changes in PR during or after meals in the pneumonia group. CONCLUSIONS This study suggests pneumonia may worsen respiratory status during meal intake. Patients with pneumonia may be unable to eat adequately due to worsened oxygenation during meals, even in the absence of aspiration. Therefore, it is important to observe whether there is a decrease in respiratory status during meals.
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Affiliation(s)
| | - Kazumichi Yonenaga
- Department of Eat-loss Medicine, Graduate School of Medicine, University of Tokyo, Hongo 7-3-1, Bunkyo-ku, Tokyo 113-8655, Japan.
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Tonosaki K, Suzuki Y, Yonenaga K, Tomimoto K, Yuzawa K, Oku S, Eto S. Infantile umbilical hernia tape fixation method without compression materials. J Gen Fam Med 2023; 24:223-230. [PMID: 37484134 PMCID: PMC10357089 DOI: 10.1002/jgf2.626] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2022] [Revised: 04/16/2023] [Accepted: 04/30/2023] [Indexed: 07/25/2023] Open
Abstract
Background Compression therapy using compression material is often used for umbilical hernias in infants; however, there are problems regarding its use, such as appearance and cost. In our hospital, we use the tape fixation method without compression materials. We report the effectiveness of this method, its significance in measuring the degree of hernia bulge before treatment, and parent satisfaction with the treatment. Methods We analyzed 77 cases of umbilical hernias (41 boys and 36 girls, mean age 52.7 ± 18.3 days) that were treated with the tape fixation method at the Department of Pediatrics of our hospital. Hernia size was classified based on the height of the bulge: mild (<1 cm), moderate (1≦ and <3 cm), or severe (>3 cm). Treatment duration was compared between the groups using the Steel-Dwass test. After the treatment, a questionnaire was mailed to the parents to assess the treatment satisfaction. Results Seventy-three patients (94.8%) achieved closure of the hernia orifice, with no excess skin and a well-shaped umbilicus. The duration of treatment was significantly shorter, with the following order: mild (18.5 ± 8.2 days), moderate (25.0 ± 11.9 days), and severe cases (47.8 ± 11.7 days). According to the questionnaire, 97.5% of the parents were satisfied with the treatment. Conclusions Our tape fixation method without compression material achieved a high closure rate and a good shape of the umbilicus. In addition, we noted that the height of the hernia bulge can be used as a guide to estimate the duration of treatment.
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Affiliation(s)
- Kanata Tonosaki
- Department of PediatricsMisawa City HospitalAomoriJapan
- Department of General MedicineTowada City HospitalAomoriJapan
- Department of Eat‐Loss Medicine, Graduate School of MedicineUniversity of TokyoTokyoJapan
| | - Yuki Suzuki
- Department of PediatricsMisawa City HospitalAomoriJapan
| | - Kazumichi Yonenaga
- Department of General MedicineTowada City HospitalAomoriJapan
- Department of Eat‐Loss Medicine, Graduate School of MedicineUniversity of TokyoTokyoJapan
| | | | | | - Shiori Oku
- Department of PediatricsMisawa City HospitalAomoriJapan
| | - Shuji Eto
- Department of PediatricsMisawa City HospitalAomoriJapan
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Ono S, Ishimaru M, Yokota I, Konishi T, Okada A, Ono Y, Matsui H, Itai S, Yonenaga K, Tonosaki K, Watanabe R, Hoshi K, Yasunaga H. Risk of post-extraction bleeding with direct oral anticoagulant compared with warfarin: Retrospective cohort study using large scale claims data in Japan. Thromb Res 2023; 222:24-30. [PMID: 36563522 DOI: 10.1016/j.thromres.2022.12.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2022] [Revised: 11/22/2022] [Accepted: 12/14/2022] [Indexed: 12/24/2022]
Abstract
INTRODUCTION Comparative safety of direct oral anticoagulants vs. warfarin in patients undergoing tooth extraction remains unclear. We compared the incidence of post-extraction bleeding between patients taking warfarin and those taking direct oral anticoagulants (DOACs) using administrative claims data. MATERIALS AND METHODS We identified outpatients on anticoagulant therapy who underwent permanent tooth extraction between 2015 and 2020 and categorized them into the warfarin and DOAC groups based on medication prescribed within six months prior to tooth extraction. We used the overlap propensity score weighting method to balance the baseline characteristics between the groups and compared the incidence of post-extraction bleeding within seven days after tooth extraction. RESULTS Among 5253 eligible patients, those in the DOAC group (n = 3696) were older and less frequently prescribed antiplatelets than those in the warfarin group (n = 1557). The distribution of tooth extraction type and number of teeth extracted in a single procedure did not differ between the groups. The unadjusted incidences of post-extraction bleeding in the warfarin and DOAC groups were 35 (2.2 %) and 71 (1.9 %), respectively. Moreover, the overlap weighting analysis showed that the adjusted odds ratio of post-extraction bleeding in the DOAC group in comparison with that in the warfarin group was 0.84 (95 % confidence interval, 0.54-1.31). CONCLUSION The incidence of post-extraction bleeding in patients taking DOACs was comparable to that in patients taking warfarin. The findings suggest that dentists and physicians should exercise the same degree of caution when extracting teeth in patients on DOACs and those on warfarin in terms of post-extraction bleeding.
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Affiliation(s)
- Sachiko Ono
- Department of Eat-loss Medicine, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8655, Japan.
| | - Miho Ishimaru
- Department of Oral Health Promotion, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8549, Japan
| | - Isao Yokota
- Department of Biostatistics, Graduate School of Medicine, Hokkaido University, Kita 15, Nishi 7, Kita-ku, Sapporo 060-8638, Japan
| | - Takaaki Konishi
- Department of Clinical Epidemiology and Health Economics, School of Public Health, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8655, Japan
| | - Akira Okada
- Department of Prevention of Diabetes and Lifestyle-Related Diseases, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8655, Japan
| | - Yosuke Ono
- Department of General Medicine, National Defense Medical College, 3-2 Namiki, Tokorozawa, Saitama 359-8513, Japan
| | - Hiroki Matsui
- Department of Clinical Epidemiology and Health Economics, School of Public Health, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8655, Japan
| | - Shunsuke Itai
- Department of Eat-loss Medicine, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8655, Japan
| | - Kazumichi Yonenaga
- Department of Eat-loss Medicine, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8655, Japan
| | - Kanata Tonosaki
- Department of Eat-loss Medicine, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8655, Japan
| | - Rinji Watanabe
- Department of Eat-loss Medicine, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8655, Japan
| | - Kazuto Hoshi
- Department of Eat-loss Medicine, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8655, Japan
| | - Hideo Yasunaga
- Department of Clinical Epidemiology and Health Economics, School of Public Health, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8655, Japan
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Tonosaki K, Yonenaga K, Itai S, Oyama S, Mizuno T, Ono S, Watanabe R, Hoshi K. Complete Lateral Positioning Enabled Feeding in a Patient with Aspiration Pneumonia. Tokai J Exp Clin Med 2022; 47:105-108. [PMID: 36073279] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Accepted: 04/14/2022] [Indexed: 06/15/2023]
Abstract
The complete lateral position can be used to widen the lateral pharynx in a direction that facilitates swallowing and reduces the risk of aspiration, even if the patient is unable to eat in the sitting position. Here, we report a case of aspiration pneumonia in a patient who was unable to eat in the sitting position after swallowing endoscopy, but was able to eat in the complete lateral position. By employing complete lateral positioning, more patients may be able to continue oral intake.
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Affiliation(s)
| | - Kazumichi Yonenaga
- Department of Eat-loss Medicine, Graduate School of Medicine, University of Tokyo, Hongo 7-3-1, Bunkyo-ku, Tokyo 113-8655, Japan.
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Tonosaki K, Yonenaga K, Itai S, Mizuno T, Oyama S. Familial Mediterranean Fever with Psychiatric Disorder which Have not Been Diagnosed over 30 Years: A Case Report. Tokai J Exp Clin Med 2021; 46:180-183. [PMID: 34859417] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Accepted: 10/11/2021] [Indexed: 06/13/2023]
Abstract
Familial Mediterranean fever (FMF) is an inherited autoimmune disease characterized by periodic fevers and serositis. Most cases have been diagnosed within 10 years or less; however, there have been no reports of cases in which diagnosis was delayed for several decades. In this study, we encountered a case of FMF in which the patient had recurrent unexplained fevers since childhood, but diagnosis was delayed for more than 30 years due to a psychiatric disorder. Our findings showed that a possible reasons for this delay are possibility of neglect or parenting skills issues, little knowledge of FMF in Japan and the lack of social connections due to the patient's underlying mental illness. We suggest that it is important to conduct a thorough medical interview to identify FMF, as it may go undiagnosed, especially when the patient has few social ties.
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Affiliation(s)
| | - Kazumichi Yonenaga
- Department of Eat-loss Medicine, Graduate School of Medicine, The University of Tokyo, Hongo 7-3-1, Bunkyo-ku, Tokyo 113-8655, Japan.
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Tonosaki K, Yonenaga K, Mikami T, Mizuno T, Oyama S. Acute Cholecystitis, Sepsis, and Disseminated Intravascular Coagulation Caused by Edwardsiella tarda in an Elderly Woman. Tokai J Exp Clin Med 2021; 46:51-53. [PMID: 33835476] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Accepted: 01/25/2021] [Indexed: 06/12/2023]
Abstract
Edwardsiella tarda is a gram-negative bacillus associated with gastrointestinal diseases. It is rarely responsible for sepsis; however, the fatality is very high. Only two cases of E. tarda infections in patients over 90 years of age have been reported; these are not cases of sepsis associated with acute cholecystitis. We report a case of acute cholecystitis, sepsis, and disseminated intravascular coagulation (DIC) caused by E. tarda in a super-elderly woman aged over 90 years. There could be a possibility for recovery from sepsis and DIC if antimicrobial treatment responsiveness is ensured in the super-elderly.
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Affiliation(s)
| | - Kazumichi Yonenaga
- Department of Eat-loss Medicine, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8655, Japan.
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Tonosaki K, Yonenaga K, Ono S, Itai S, Oyama S, Mizuno T, Watanabe R, Hoshi K. Swallowing evaluation by the Kuchikara Taberu Balance Chart and videoendscopic examination reveals that respiratory conditions, chewing, and position are strongly related to dysphagia. Odontology 2020; 109:448-452. [PMID: 33108554 DOI: 10.1007/s10266-020-00561-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2020] [Accepted: 10/15/2020] [Indexed: 10/23/2022]
Abstract
This study focused on the Kuchikara Taberu Balance Chart (KTBC) as a tool for swallowing function evaluation. To clarify the relationship between videoendoscopic (VE) examination of swallowing function and the KTBC, we compared median KTBC scores with and without laryngeal penetration identified by VE. Sixty-five patients with a mean age of 84.3 ± 7.9 years were examined at the Towada City Hospital. The patients were classified into groups based on laryngeal penetration, including 28 patients with and 37 patients without penetration. We found no significant differences in patient backgrounds. The median KTBC score (interquartile range) was 36.5 (31-44.5) in the group with laryngeal penetration and 42 (35-48.5) in the group without penetration, but the scores were not significantly different (level of statistical significance at α = 0.0036 determined by the Bonferroni correction method) when compared with the Mann-Whitney U test (36.5 vs. 42, z = -2.33, p = 0.020). The median respiratory condition (3 vs. 4, z = - 3.23; p < 0.0036), oral preparatory and propulsive phases (3 vs. 4, z = - 2.96; p < 0.0036), and position and endurance (1 vs. 3, z = - 3.25; p < 0.0036) scores were significantly lower in the group with laryngeal penetration. This study revealed a correlation between laryngeal penetration confirmed by VE and KTBC scores. Consequently, respiratory condition, oral preparatory and propulsive phases, and position and endurance may be useful as tools for the assessment of swallowing. In particular, we recommend adding respiratory status to dysphagia screening.
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Affiliation(s)
- Kanata Tonosaki
- Department of Eat-Loss Medicine, Graduate School of Medicine, The University of Tokyo, Hongo 7-3-1, Bunkyo-ku, Tokyo, 113-8655, Japan.,Department of General Medicine, Towada City Hospital, Aomori, Japan
| | - Kazumichi Yonenaga
- Department of Eat-Loss Medicine, Graduate School of Medicine, The University of Tokyo, Hongo 7-3-1, Bunkyo-ku, Tokyo, 113-8655, Japan. .,Department of General Medicine, Towada City Hospital, Aomori, Japan.
| | - Sachiko Ono
- Department of Eat-Loss Medicine, Graduate School of Medicine, The University of Tokyo, Hongo 7-3-1, Bunkyo-ku, Tokyo, 113-8655, Japan
| | - Shunsuke Itai
- Department of Eat-Loss Medicine, Graduate School of Medicine, The University of Tokyo, Hongo 7-3-1, Bunkyo-ku, Tokyo, 113-8655, Japan
| | - Shigeto Oyama
- Department of General Medicine, Towada City Hospital, Aomori, Japan
| | - Takashi Mizuno
- Department of General Medicine, Towada City Hospital, Aomori, Japan
| | - Rinji Watanabe
- Department of Eat-Loss Medicine, Graduate School of Medicine, The University of Tokyo, Hongo 7-3-1, Bunkyo-ku, Tokyo, 113-8655, Japan
| | - Kazuto Hoshi
- Department of Oral-Maxillofacial Surgery, Dentistry and Orthodontics, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
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Tonosaki K, Michiba K, Bang SW, Kitashiba H, Kaneko Y, Nishio T. Genetic analysis of hybrid seed formation ability of Brassica rapa in intergeneric crossings with Raphanus sativus. Theor Appl Genet 2013. [PMID: 23203221 DOI: 10.1007/s00122-012-2021-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
A hybridization barrier leads to the inability of seed formation after intergeneric crossings between Brassica rapa and Raphanus sativus. Most B. rapa lines cannot set intergeneric hybrid seeds because of embryo breakdown, but a B. rapa line obtained from turnip cultivar 'Shogoin-kabu' is able to produce a large number of hybrid seeds as a maternal parent by crossings with R. sativus. In 'Shogoin-kabu' crossed with R. sativus, developments of embryos and endosperms were slower than those in intraspecific crossings, but some of them grew to mature seeds without embryo breakdown. Intergeneric hybrid seeds were obtained in a 'Shogoin-kabu' line at a rate of 0.13 per pollinated flower, while no hybrid seeds were obtained in a line developed from Chinese cabbage cultivar 'Chiifu'. F(1) hybrid plants between the lines of 'Shogoin-kabu' and 'Chiifu' set a larger number of hybrid seeds per flower, 0.68, than both the parental lines. Quantitative trait loci (QTLs) for hybrid seed formation were analyzed after intergeneric crossings using two different F(2) populations derived from the F(1) hybrids, and three QTLs with significant logarithm of odds scores were detected. Among them, two QTLs, i.e., one in linkage group A10 and the other in linkage group A01, were detected in both the F(2) populations. These two QTLs had contrary effects on the number of hybrid seeds. Epistatic interaction between these two QTLs was revealed. Possible candidate genes controlling hybrid seed formation ability in QTL regions were inferred using the published B. rapa genome sequences.
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Affiliation(s)
- K Tonosaki
- Graduate School of Agricultural Science, Tohoku University, 1-1 Tsutsumidori-Amamiyamachi, Aoba-ku, Sendai, Miyagi 981-8555, Japan
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Tonosaki K, Nishio T. Identification of species in tribe Brassiceae by dot-blot hybridization using species-specific ITS1 probes. Plant Cell Rep 2010; 29:1179-1186. [PMID: 20683723 DOI: 10.1007/s00299-010-0904-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2010] [Revised: 07/12/2010] [Accepted: 07/18/2010] [Indexed: 05/28/2023]
Abstract
Simple, reliable methods for identification of species are required for management of many species and lines in a plant gene bank. Species-specific probes were designed from published sequences of the ITS1 region in rDNA of 16 species in Brassica and its related genera, and used as probes for dot-blot hybridization with plant genomic DNA. All the probes detected species-specific signals at dot-blots of genomic DNAs of the 16 species in Brassica, Diplotaxis, Eruca, and Raphanus. Signals of the Brassica digenomic species in the U's triangle, i.e., B. napus, B. juncea, and B. carinata, were detected by the probes of their parental monogenomic species, i.e., B. rapa, B. nigra, and B. oleracea. The probe for B. oleracea showed signals of B. balearica, B. cretica, B. incana, B. insularis, and B. macrocarpa, which have the C genome as B. oleracea. Eruca vesicaria DNA was detected by the probe for E. sativa, which has been classified as a subspecies of E. vescaria. DNA of leaf tissue extracted by an alkaline solution and seed DNA prepared by the NaI method can be used directly for dot-blotting. Misidentification of species was revealed in 20 accessions in the Tohoku University Brassica Seed Bank. These results indicate dot-blot hybridization to be a simple and efficient technique for identification of plant species in a gene bank.
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Affiliation(s)
- K Tonosaki
- Graduate School of Agricultural Science, Tohoku University, 1-1 Tsutsumidori-Amamiyamachi Aoba-ku, Sendai, Miyagi 981-8555, Japan
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Abstract
OBJECTIVE AND DESIGN Free radicals/reactive oxygen species (ROS) are related to inflammation, aging, and cancer. However, living systems have essential antioxidant mechanisms by which these harmful radicals can be scavenged, i.e., free radical-scavenging activity (FRSA). We measured the circadian rhythm of such activities by detecting salivary FRSA in healthy adults, and also examined how salivary FRSA is affected by physical and mental activities, which included (1) ingestion of beverage, (2) exercise, (3) comfortable/uncomfortable stimulation, and (4) smoking. METHODS FRSA was determined by using the DPPH (1,1'-diphenyl-2-picrylhydrazyl) method. Statistical analysis for experimentally obtained median values was carried out using the Wilcoxon signed rank test. RESULTS In circadian rhythm, FRSA was increased by food ingestion and relaxation. As to the individual activities, green tea and coffee ingestion increased FRSA, whereas swimming (P < 0.05) and dance lessons (P < 0.01) decreased it. Watching an amusing video program (P < 0.001) or stimulation by a pleasant aroma (P < 0.01) increased FRSA. In contrast, an unpleasant odor had no effect on FRSA. FRSA decreased immediately after smoking (P < 0.05), but increased thereafter (P < 0.01). CONCLUSION Salivary FRSA was affected not only by physical activities, but also by mental activities. It may be a parameter for reflecting the health status of individuals.
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Affiliation(s)
- T Atsumi
- Department of Human Development & Fostering, Meikai University School of Dentistry, Saitama, Japan
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Atsumi T, Fujisawa S, Tonosaki K. (Meth)acrylate monomer-induced cytotoxicity and intracellular Ca2+ mobilization in human salivary gland carcinoma cells and human gingival fibroblast cells related to monomer hydrophobicity. Biomaterials 2006; 27:5794-800. [PMID: 16934868 DOI: 10.1016/j.biomaterials.2006.07.041] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2006] [Accepted: 07/31/2006] [Indexed: 11/28/2022]
Abstract
To elucidate a possible link between the cytotoxicity and Ca(2+) mobilization by (meth)acrylates, we investigated the cell survival of and change in [Ca(2+)](i) in human salivary gland (HSG) cells (salivary gland carcinoma cell line) and human gingival fibroblasts (HGF) cells treated separately with 9 (meth)acrylate monomers used in dentistry. The cell survival was determined by the MTT method, and the [Ca(2+)](i) changes after the stimulation with the (meth)acrylate monomers were measured in floating indo-1/AM-loaded cells in Ca(2+)-free medium. For both HSG and HGF cells, the cytotoxicity of the monomers was approximately proportional to their hydrophobicity (logP). No increase in [Ca(2+)](i) was found with hydrophilic monomers, even with 10mm stimulation. [Ca(2+)](i) elevation by hydrophobic monomers occurred in a dose- and hydrophobic-dependent manner. The [Ca(2+)](i) change in HSG cells appeared as twin peaks, i.e., an initial sharp peak followed by a delayed broad one; whereas with the HGF cells only a single broad peak was seen, possibly dependent on their membrane quality. Pretreatment with n-butanol or methylmethacrylate enhanced the butylmethacrylate-induced [Ca(2+)](i) elevation, suggesting the [Ca(2+)](i) elevation by (meth)acrylate may be related to monomer hydrophobicity and cell type. The causal link between the cytotoxicity and [Ca(2+)](i) mobilization of monomers is discussed.
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Affiliation(s)
- Toshiko Atsumi
- Department of Oral Physiology, Meikai University, School of Dentistry, 1-1, Keyakidai, Sakado, Saitama 350 0283, Japan.
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13
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Atsumi T, Fujisawa S, Tonosaki K. Relationship between intracellular ROS production and membrane mobility in curcumin- and tetrahydrocurcumin-treated human gingival fibroblasts and human submandibular gland carcinoma cells. Oral Dis 2005; 11:236-42. [PMID: 15984955 DOI: 10.1111/j.1601-0825.2005.01067.x] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
OBJECTIVE Curcumin is a well-known chemopreventive agent of oral cancers as well as stomach and intestinal cancers. The relationship between reactive oxygen species (ROS) production and cell membrane mobility was investigated to clarify the pro-oxidant mechanism of curcumin and tetrahydrocurcumin (TH-curcumin). METHODS The intracellular ROS production and membrane mobility by curcumin or TH-curcumin were measured in human submandibular adenocarcinoma cells (HSGs) and human primary gingival fibroblasts (HGFs). ROS and mobility were measured by 5-(and -6)-carboxy-2',7'-dichlorofluorescein diacetate staining and fluorescence recovery after photo bleaching, respectively. RESULTS Curcumin produced ROS dose-dependently. ROS appeared in the region surrounding the cell membrane. The membrane mobility coefficient of the curcumin-treated cells was significantly lower than that of control cells. The lowered membrane mobility induced by curcumin was reversed by the addition of glutathione, an antioxidant. In contrast, TH-curcumin did not affect the ROS production or the membrane mobility coefficient. The alternations induced by curcumin treated HSG cells were greater than those by HGF cells. CONCLUSION The reduction in membrane mobility induced by curcumin was attributed to ROS production. The oxidative effects of curcumin may be related to the structure of the alpha, beta-unsaturated carbonyl moiety as well as the phenolic OH group of this compound.
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Affiliation(s)
- T Atsumi
- Department of Oral Physiology, Meikai University School of Dentistry, Keyakidai, Sakado-shi, Saitama, Japan.
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14
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Atsumi T, Fujisawa S, Tonosaki K. A comparative study of the antioxidant/prooxidant activities of eugenol and isoeugenol with various concentrations and oxidation conditions. Toxicol In Vitro 2005; 19:1025-33. [PMID: 15964168 DOI: 10.1016/j.tiv.2005.04.012] [Citation(s) in RCA: 82] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2004] [Revised: 04/23/2005] [Accepted: 04/25/2005] [Indexed: 11/20/2022]
Abstract
Eugenol (compound in , 4-allyl-2-methyoxyphenol) and isoeugenol (compound in , 4-propenyl-2-methoxyphenol), both used as a flavor agent in cosmetic and food products, have both prooxidant and antioxidant activities. Their adverse effects such as allergic and inflammatory reaction may be due to their prooxidant activity. To clarify the mechanisms of their cytotoxicity and the factors affecting their antioxidant/prooxidant activities, we investigated the cytotoxicity, ROS production, and cellular glutathione (GSH) levels induced by eugenol and isoeugenol in a human submandibular cell line. The cytotoxicity (MTT method) of eugenol was 1 order of magnitude lower than that of isoeugenol (CC50: eugenol, 0.395 mM; isoeugenol, 0.0523 mM); and ROS production (CDF staining) was induced significantly by isoeugenol, but not by eugenol. Under treatment with H2O2 (100 microM) plus horseradish peroxidase (1 microg/ml) for 30 min or with visible light irradiation for 5 min, eugenol caused biphasic ROS production characterized by enhanced at lower eugenol concentrations (5-10 microM) and decreased at higher concentrations (500 microM). In contrast, isoeugenol enhanced ROS production over a wide range of concentrations (5-500 microM). Isoeugenol at 1000 microM significantly reduced GSH levels compared with eugenol at the same concentration. The high cytotoxicity of isoeugenol may be attributed to its induction of high ROS production and low GSH levels, possibly as a result of benzyl radical formation. In contrast, the cytotoxicity of eugenol is likely to be mediated by ROS-independent mechanisms, possibly involving phenoxyl radicals and/or eugenol quinone methide.
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Affiliation(s)
- T Atsumi
- Department of Oral Physiology, Meikai University School of Dentistry, 1-1, Keyakidai, Sakado-shi, Saitama 350-0283, Japan.
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15
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Atsumi T, Ishihara M, Kadoma Y, Tonosaki K, Fujisawa S. Comparative radical production and cytotoxicity induced by camphorquinone and 9-fluorenone against human pulp fibroblasts. J Oral Rehabil 2004; 31:1155-64. [PMID: 15544650 DOI: 10.1111/j.1365-2842.2004.01357.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Camphorquinone (CQ) is widely used as a photo-initiator in dental materials; however, its cytotoxicity against human pulp fibroblasts (HPF) and particularly the effects of 2-dimethylaminoethyl methacrylate (DMA), a reducing agent and visible light (VL) irradiation on it remain unknown. So we investigated the cytotoxic and reactive oxygen species (ROS)-producing effects of CQ with or without DMA, in the presence or absence of VL on HPF cells. The free-radical production activity of CQ was measured by two different methods [using diphenylpicryl hydrazyl and galvinoxyl]. The phase-transition properties of dipalmitoylphosphatidyl choline (DPPC) liposomes, as a model for biomembranes, induced by CQ were investigated by differential scanning calorimetry. These findings were compared with those of 9-fluorenone (9F), an aromatic photo-initiator with long conjugated groups. Camphorquinone with VL irradiation increased the radical production, whereas 9F with VL irradiation increased ROS production, as well as effecting changes in the DPPC phase-transition properties. The cytotoxicity of CQ towards HPF cells was smaller than that of 9F despite greater radical production. The addition of DMA to the photosensitizer enhanced the free-radical production without increasing the ROS level or the cytotoxicity. Camphorquinone/DMA is a valuable combination for the polymerization of dental resins.
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Affiliation(s)
- T Atsumi
- Department of Oral Physiology, Mekai University School of Dentistry, Sakado, Saitama, Japan.
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16
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Atsumi T, Fujisawa S, Nakabayashi Y, Kawarai T, Yasui T, Tonosaki K. Pleasant feeling from watching a comical video enhances free radical-scavenging capacity in human whole saliva. J Psychosom Res 2004; 56:377-9. [PMID: 15046977 DOI: 10.1016/s0022-3999(03)00064-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/02/2002] [Accepted: 03/04/2003] [Indexed: 11/21/2022]
Abstract
OBJECTIVE Free radicals have been implicated in aging, mutagenesis, inflammation and other pathological conditions. We conducted a study to clarify the relation between a pleasant feeling as a psychological eustress and free radical-scavenging capacity (FRSC) in saliva. METHODS Saliva was collected from 27 healthy volunteers. FRSC before, during and after watching a cheerful comical video for 30 min was measured by using 1,1-diphenyl-2-picrylhydrazyl (DPPH). RESULTS The median values of FRSC (micromol/ml) before, at 10 and 20 min during and after watching the video were 54.5, 66.8, 66.6 and 69.4, respectively. The FRSC values obtained after watching the video were significantly higher than those before watching it (P<.001). When the FRSC before watching was taken as 1, the value for the group that felt "Very good," "Good" or "Ordinary+Dull" while watching the video for 30 min was 1.38, 1.20 or 0.98, respectively (P<.01). CONCLUSION Watching a comical video enhanced the FRSC in saliva; in addition, a pleasant feeling boosted it even more.
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Affiliation(s)
- T Atsumi
- Department of Oral Physiology, Meikai University School of Dentistry, 1-1, Keyakidai, Sakado, Saitama 350-0283, Japan.
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17
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Abstract
The importance of taste and smell in discrimination of tastes was examined in normal and anosmic mice. We studied the influence of olfaction on taste sensation using behavioral and electrophysiological methods in both normal animals and animals made anosmic mice by destroying their olfactory receptor cells with zinc sulfate (ZnSO(4)) solution. Electrophysiological responses from chorda tympani nerves showed that peripheral taste receptor cells transmitted taste signals normally to the central nervous system, even when the olfactory senses were abnormal. Behavioral observations showed that mice with abnormal olfaction could not differentiate tastes.
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Affiliation(s)
- H Uebayashi
- Department of Veterinary Physiology, Faculty of Agriculture, Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan
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18
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Watanabe K, Tonosaki K, Kawase T, Karasawa N, Nagatsu I, Fujita M, Onozuka M. Evidence for involvement of dysfunctional teeth in the senile process in the hippocampus of SAMP8 mice. Exp Gerontol 2001; 36:283-95. [PMID: 11226743 DOI: 10.1016/s0531-5565(00)00216-3] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
In order to evaluate the involvement of dysfunctional teeth in age-related deficits in hippocampal function, we examined the effect of removal of molar teeth (molarless condition) on neuronal degeneration and glial fibrous acidic protein (GFAP) expression in the hippocampus and on learning ability in a water maze test in young, middle-aged, and aged accelerated senescence-prone mice (SAMP8). The molarless condition enhanced an age-dependent decrease in both learning ability and the number of neurons in the hippocampal CA1 subfield and the age-dependent increase in the number and hypertrophy of GFAP-labeled astrocytes in the same subfield. These observations suggest that the molarless condition may be involved in the senile process in the hippocampus in SAMP8 mice.
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Affiliation(s)
- K Watanabe
- Department of Physiology, Gifu University School of Medicine, 500-8705, Gifu, Japan
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19
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Abstract
Scientists in many fields have studied olfaction in dogs, but no simple method exists to study this function. The olfactory ability of dogs is used in many fields. However, the owners of the dogs have a frustrating experience because there is not an easy method to measure olfactory function. The purpose of this study was to examine the characteristics of olfactory function of the dog with electroencephalographic olfactometry (EEGO) recording. It was found that slow waves decreased and rapid waves increased in response to odours. From these results, it is suggested that the rapid waves of EEGO activity are important in determining a dog's olfactory ability. The EEGO recording is effective in diagnosing anosmia in the dog and is easier than a behavioural experiment. Additionally, this method may not cause distress to an animal.
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Affiliation(s)
- Y Hirano
- Department of Veterinary Physiology, Faculty of Agriculture, Gifu University, 1-1 Yanagido, Gifu, Gifu 501-1193, Japan
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20
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Abstract
Although avian olfaction has been studied behaviorally and anatomically, few electrophysiological (EEG) studies exist. The purpose of this study is to examine the characteristics of the olfactory function of the fowl with EEG recording. We found that slow waves decreased and the rapid waves increased in response to a variety of odors.
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Affiliation(s)
- T Oosawa
- Department of Veterinary Physiology, Faculty of Agriculture, Gifu University, 1-1 Yanagido, Gifu, 501-1193, Gifu, Japan
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21
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Nakayasu C, Kanemura F, Hirano Y, Shimizu Y, Tonosaki K. Sensitivity of the olfactory sense declines with the aging in senescence-accelerated mouse (SAM-P1). Physiol Behav 2000; 70:135-9. [PMID: 10978488 DOI: 10.1016/s0031-9384(00)00234-1] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The decline in olfaction with age is well documented in histological, psychological, and electroencephalographical studies. However, there are few electrophysiological studies on changes in the sensitivity of the peripheral olfactory cells with age. We evaluated the behavior, the amplitude of electro-olfactogram (EOG), and the thickness of the olfactory epithelium in the Senescence-Accelerated Mouse (SAM-P1). This strain of mouse exhibits accelerated senescence and age-related pathologies, and it is commonly used as a model for research on aging. Its median survival time is 55 weeks. To ensure our results would be restricted to the olfactory system, we chose vanillin as a stimulus, because this stimulus has no definitive chorda tympani (VII) response, and we verified that it is tasteless. The data demonstrate that olfactory sensitivity to vanillin decreases dramatically with age in these mice, and that this is due to loss in the number of olfactory receptor cells.
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Affiliation(s)
- C Nakayasu
- Department of Veterinary Physiology, Faculty of Agriculture, Gifu University, 1-1 Yanagido, Gifu, 501-1193, Gifu, Japan
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22
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Ogiso K, Shimizu Y, Watanabe K, Tonosaki K. Possible involvement of undissociated acid molecules in the acid response of the chorda tympani nerve of the rat. J Neurophysiol 2000; 83:2776-9. [PMID: 10805675 DOI: 10.1152/jn.2000.83.5.2776] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
To test whether undissociated acid is capable of exciting the chorda tympani nerves in rats, we have used buffered acid solutions as taste stimuli. These solutions were prepared by adding alkali to weak acids, such as acetic acid, so that the proportion of undissociated and dissociated acids was varied whereas keeping the total acid concentration constant. When acetic acid solutions, adjusted to wide ranges of pH by NaOH, were applied to the tongue, the response magnitude of the chorda tympani nerves was not varied systematically with pH changes. However, if the sodium effect was eliminated by amiloride or replacement of cation by potassium or Tris[hydroxymethyl]aminomethane; NH(2)C(CH(2)OH)(3) (Tris-base), the chorda tympani response was reduced systematically as pH increased. Similar results were obtained with citric acid and ascorbic acid. This pH-dependent change in taste nerve response to acid cannot be solely attributed to the proton gradient because the response magnitude induced by hydrogen itself, which was estimated from responses to strong acids, was much smaller than that by equi-pH acetic acid ( approximately 85%). Thus we cannot explain the pH-dependent responses of the chorda tympani nerves to weak acids unless effects of undissociated acid molecules are postulated. It is therefore concluded that undissociated acids in weak acid solutions can be a stimulant to taste receptor cells.
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Affiliation(s)
- K Ogiso
- Department of Veterinary Physiology, Faculty of Agriculture, Gifu University, Gifu 501-1193, Japan
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23
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Abstract
The purpose of this study is whether the gustatory neural response of taste cell to a binary mixture with threshold concentration of acid becomes synergistic or antagonistic can be estimated from the whole chorda tympani (CT) nerve in the rat. The present data demonstrate that acids are synergistic enhancer for sugars, and suppressor for NaCl and QHCl, but no effect to glycine and alanine. These results suggest that the acid was modifying the interaction of the other stimulus with its transduction mechanism.
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Affiliation(s)
- N Sakurai
- Department of Veterinary Physiology, Faculty of Agriculture, Gifu University, 1-1 Yanagido, Gifu, Gifu, Japan
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24
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25
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Abstract
We studied the effects of cold ambient temperature on chorda tympani nerve responses to taste stimuli such as sucrose, NaCl, quinine HCl (QHCl), and HCl in rats. The electrophysiological recordings of the whole chorda tympani nerves from control (22 degrees C) and cold-exposed (4 degrees C) rats revealed that the responses to sucrose, HCl, and QHCl were unaffected by cold exposure. In contrast, the nerve responses to NaCl were enhanced time dependently, reaching a maximum 7-14 days after cold exposure. Responses to sodium acetate were likewise elevated as they were to NaCl, whereas those to KCl were unchanged after cold exposure. In addition, the residual NaCl responses after lingual application of the sodium-channel blocker amiloride in cold-exposed rats were similar to those in control animals. It is thus most likely that cold exposure potentiates the chorda tympani nerve responses to Na(+), but not to Cl(-). Behavioral studies with the two-bottle preference test showed that the cold-exposed rats refused to drink NaCl solutions at 0.05 and 0.1 M, the concentrations being preferred by control animals. These results suggest that the ambient temperature influences taste cell function, and that the enhanced NaCl response of the chorda tympani nerve is related to the avoidance of NaCl intake under cold environment.
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Affiliation(s)
- Y Shimizu
- Department of Veterinary Physiology, Faculty of Agriculture, Gifu University, Gifu 501-1193, Japan
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26
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Abstract
The sweetness-suppressing polypeptide gurmarin isolated from Gymnema sylvestre consists of 35 amino acid residues and includes three intramolecular disulfide bonds. The roles of the three disulfide bonds were investigated by replacing each with two alanine residues by solid-phase synthesis. Nine analogues of [Ala3,18]gurmarin, [Ala10,23]gurmarin, and [Ala17,33]-gurmarin were obtained. Three analogues had native disulfide bonds, while the other six had non-native disulfide bonds. The three analogues with native disulfide bonds suppressed the response to sucrose, but not those to glucose, fructose, saccharin, or glycine in rats. In contrast, the six analogues with non-native disulfide bonds did not suppress the responses to any of these sweeteners. These results suggest that the native disulfide bonds of gurmarin are necessary for interaction with the receptor protein, and that the sucrose-specific receptor site is present in rats.
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Affiliation(s)
- M Ota
- Central Research Laboratories, Ajinomoto Co., Inc., Kawasaki, Japan
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27
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Abstract
The sweetness-suppressing polypeptide gurmarin isolated from Gymnema sylvestre consists of 35 amino acid residues and contains three intramolecular disulfide bonds. Nuclear magnetic resonance analysis showed that the hydrophobic side chains of Tyr-13, Tyr-14, Trp-28, and Trp-29 in gurmarin are oriented outwardly. Together with the hydrophobic side chains of Leu-9, Ile-11, and Pro-12, they form a hydrophobic cluster, and therefore these hydrophobic groups are assumed to act as the site for interaction with the receptor protein. To examine the roles of these hydrophobic amino acids, they were replaced by Gly. The resulting [Gly13,14,28,29] gurmarin and [Gly9,11,13,14,28,29]-gurmarin did not suppress the responses to sucrose, glucose, fructose, or Gly. This result strongly suggests that these hydrophobic amino acids are involved in the interaction with the receptor protein.
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Affiliation(s)
- M Ota
- Central Research Laboratories, Ajinomoto Co., Inc., Kawasaki, Japan
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28
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Abstract
Mouse gustatory responses to sucrose, monellin and thaumatin were examined extracellularly from the chorda tympani nerve and intracellularly from individual taste receptor cells. Although monellin and thaumatin taste intensely sweet to humans and old-world monkeys, they do not appear to elicit chorda tympani nerve responses in rats and other mammals. However, there is considerable species variation in the taste responses of mammals, including differences in taste responses of different strains of mice. In the present study with Slc:ICR mice, we show that chorda tympani and taste receptor cell response profiles, and behavioral results for monellin and thaumatin, are similar to response profiles for sucrose.
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Affiliation(s)
- K Tonosaki
- Department of Veterinary Physiology, Faculty of Agriculture, Gifu University, Japan. tonosaki_at_cc.dec.aedu.gifu-u.ac.jp
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29
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Abstract
Taste signal transduction occurs in the microvillous membrane of taste cells. Previously, we hypothesized that c-GMP may mediate sweet taste transduction. Some data indicated that IP3 may have a role in vertebrate bitter taste transduction. Here we report that the different second messengers are activated by different tastes. We used techniques designed for radioimmunoassay measurement. The results indicate that sucrose triggers an increase in c-GMP concentration and quinine increases the IP3 concentration in mouse taste cells. These results support the sweet and bitter taste transduction hypotheses.
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Affiliation(s)
- K Miwa
- Department of Oral Physiology, School of Dentistry, Asahi University, Gifu, Japan
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30
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Ota M, Tonosaki K, Miwa K, Fukuwatari T, Ariyoshi Y. Synthesis and characterization of the sweetness-suppressing polypeptide gurmarin and ent-gurmarin. Biopolymers 1996; 39:199-205. [PMID: 8679949 DOI: 10.1002/(sici)1097-0282(199608)39:2%3c199::aid-bip8%3e3.0.co;2-k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The sweetness-suppressing polypeptide gurmarin isolated from the leaves of Gymnema sylvestre consists of 35 amino acid residues including three intramolecular disulfide bonds. Herein, the total chemical synthesis of gurmarin was performed by the stepwise fluoren-9-ylmethoxy-carbonyl solid-phase method, the yield of reduced gurmarin being 1.9% based on the starting amino acid resin. Disulfide formation was carried out in the presence of a redox system of reduced glutathione/oxidized glutathione to give gurmarin in a yield of 35.5%. The product was identical to natural gurmarin by analytical reverse phase high performance liquid chromatography (RP-HPLC), mass spectroscopy (MS), and peptide mapping, and suppressed the responses to sucrose, D-glucose, and L-glucose in a rat. The D enantiomer (all D-amino acid gurmarin) was also synthesized, and was shown to be the mirror image of gurmarin. Interestingly, the D enantiomer (ent-gurmarin) also suppressed the responses to sucrose, D-glucose, and L-glucose in a rat.
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Affiliation(s)
- M Ota
- Central Research Laboratories, Ajinomoto Co., Inc. Kawasaki, Japan
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31
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Abstract
The chorda tympani nerve (CT) and the glossopharyngeal nerve (GL) have been considered important nerves for the sense of taste. We studied the effect of bilateral sectioning of the CT and/or GL on the sweet taste in the mouse. Before and after surgery we analyzed the daily drinking patterns, using the two-bottle preference test method. The normal mouse drank the low concentration sucrose solution (0.0125 M) more than distilled water. This report showed that the mouse who was bilateral sectioned, both CT and GL or bilateral sectioned CT, rejected drinking the low concentration of sucrose solution. In contrast, the mouse who was bilateral sectioned GL drank the low concentration sucrose solution like the normal mouse did. These phenomena suggested that the fungiform papilae play an important role to detect the low concentration of sucrose (0.0125 M) as a sweet favorable taste substance.
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Affiliation(s)
- K Tonosaki
- Department of Oral Physiology, School of Dentistry, Asahi University, Gifu, Japan
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32
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Abstract
Electrical recording from small twigs of olfactory nerve and electro-olfactogram (EOG) from olfactory epithelium in a turtle shows that olfactory receptors in the nose are responsive to various odors. I have used the effects of cross-adaptation to odor stimulation on the olfactory receptors to investigate the stimulus-specific components of these responses and to provide information about the responsiveness of cells. The results of the cross-adaptation experiments strongly support the hypothesis that different categories of receptor cells exist in the olfactory epithelium.
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Affiliation(s)
- K Tonosaki
- Department of Oral Physiology, School of Dentistry, Asahi University, Gifu, Japan
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33
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Abstract
1. Intracellular recordings from mouse taste receptor cells were made to study cellular adaptation properties. 2. The sugar and salt receptor mechanisms of mammalian taste cells were investigated with cross-adaptation experiments. 3. The responding of taste cells to sucrose as well as to NaCl does not contradict the independency of their binding mechanisms. 4. With a mixture of sucrose and NaCl, different adsorption mechanisms are observed. 5. From these observations, it was concluded that adaptation occurs in the taste receptor cell.
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Affiliation(s)
- K Tonosaki
- Department of Oral Physiology, School of Dentistry, Asahi University, Gifu, Japan
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34
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Abstract
The exact nature of taste adaptation is not known. Intracellular recordings from taste receptor cells are appropriate to clarify cellular adaptation properties. I approached the study of the sugar and salt receptor mechanisms of mammalian taste cells with cross-adaptation experiments. Sucrose pre-adaptation suppresses the cross-adaptation responses to salts. The results show that the taste adaptation is located in the taste receptor cell.
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Affiliation(s)
- K Tonosaki
- Department of Oral Physiology, School of Dentistry, Asahi University, Gifu, Japan
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35
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Affiliation(s)
- K Tonosaki
- Dept. of Oral Physiology, Sch. of Dentistry, Asahi University, Gifu, Japan
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36
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Abstract
1. Intracellular recordings of mouse taste cell responses were made using a glass micro-electrode filled with Procion yellow dye solution. 2. Six sugars (sucrose, maltose, lactose, glucose, galactose and fructose) produced the depolarization responses. 3. Gustatory cross adaptation between sugars was determined. When the taste cell was pre-adapted with one of the six sugars, the other five sugars, cross adapted, produced depolarization, hyperpolarization or null responses. 4. From these observations, it is suggested that there are multiple sugar receptor sites on the receptor membrane of the mouse taste cell.
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Affiliation(s)
- K Tonosaki
- Department of Oral Physiology, School of Dentistry, Asahi University, Gifu, Japan
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37
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Abstract
Intracellular recordings were obtained using the current-clamp and voltage-clamp techniques. When the taste cell membrane was voltage-clamped, the sucrose stimulus induced an inward current accompanied by a membrane resistance increase while the NaCl stimulus induced an inward current accompanied by a membrane resistance decrease. These phenomena indicated that sucrose and NaCl have quite a different generation mechanism of taste responses.
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Affiliation(s)
- K Tonosaki
- Department of Oral Physiology, School of Dentistry, Asahi University, Gifu, Japan
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38
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Abstract
Taste stimulus adsorption is believed to occur at the taste cell microvillous membrane. But due to technical difficulties of inserting glass electrodes into the mammalian taste cell, little is known about the mechanisms of taste transduction. Reliable intracellular recordings are necessary to determine the characteristics of taste cells. This has been accomplished previously in the mouse and is reported here. Recent experiments indicated that cyclic nucleotides can act on the inner surface of the membranes of a variety of cells to alter their ion-channel activity, and these substances might act as intracellular transmitters in taste cells. But tight junctions found at the apical membrane of mammalian taste cells do not allow stimuli to enter the taste bud, making it difficult to alter the environment of the taste cell by perfusing with chemical solutions. Here we report that cyclic AMP, cyclic GMP, EGTA or tetraethyl-ammonium electrophoretically injected into the mouse taste cell induce membrane depolarization and increased membrane resistance. These results suggest that a cyclic nucleotide enzymatic cascade, modulated by calcium ions, may mediate the potassium permeability that controls taste, in a way analogous to visual and olfactory transduction.
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Affiliation(s)
- K Tonosaki
- Department of Oral Physiology, School of Dentistry, Asahi University, Gifu, Japan
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Tonosaki K, Shibuya T. The effect of some drugs on the mitral cell odor-evoked responses in the gecko olfactory bulb. Comp Biochem Physiol C Comp Pharmacol Toxicol 1985; 80:361-70. [PMID: 2861022 DOI: 10.1016/0742-8413(85)90069-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The activity of odor-evoked olfactory mitral cell response of the gecko was recorded extracellularly by glass microelectrodes. The activities of the mitral cell observed during the presentation of the odor (n-amyl acetate) could be described as excitation, suppression or zero. The present experiments were undertaken to study the neural activities of the mitral cell in the olfactory bulb by perfusion application of some drugs (cobalt chloride, carnosine, norepinephrine, GABA and D-L-homocysteate) on the olfactory bulb surface or iontophoretic application of some drugs (carnosine, norepinephrine, GABA and D-L-homocysteate) to the glomerulus and the external plexiform layer to change the physiological environment. The effect of the drugs suggested that the synaptic neurons on the mitral cell have different chemical characteristics.
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Abstract
A preparation has been developed in the dog which allows recording the electrical activity from an olfactory nerve twig containing the axons of a small group of olfactory receptor cells. The dog's response to n-pentyl acetate is vigorous and stable, like that of other air-breathing animals. The dog's response magnitude dependence on the nasal flow rate was noticeable for n-pentyl acetates, but not so great as for n-butyric acid. The response to n-butyric acid strongly depends on the nasal flow. The start of the nasal air flow caused an increase of neural activity, which is called flow response. The results show that the nasal flow rate is a very important factor which determines the response to odors. Methyl p-hydroxybenzoate is known as a dog's pheromone, however, this odor caused the feeble response in the electrical activity of the dog's olfactory receptor cells. The differences may be dependent on several factors.
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Abstract
A preparation has been developed in the pigeon which allows recording of the electrical activity from an olfactory nerve twig containing the nonmyelinated axons of a small group of olfactory receptor cells. The pigeon's response to n-amylacetate is vigorous and stable, like that of other air-breathing animals. Responses in the olfactory receptor cells in the pigeon increased in magnitude with increase in the odor concentration. An olfactory nerve twig produced a different magnitude of responses to the various odor stimuli. When an odor stimulation was applied to the olfactory mucosa, the two different olfactory nerve twigs which were separated from the same olfactory nerve bundle produced a different magnitude of responses. The differences may be dependent on several factors.
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Abstract
Intracellular recordings of membrane potentials of taste cells in mouse taste bud were made using a glass microelectrode filled with procion yellow dye solution. The recorded taste cell was injected with procion yellow dye solution. Each taste bud preparation was observed under a fluorescence microscope and if a stained taste cell was not found in the taste bud preparation, the responses were negated. Sucrose produced a depolarization response and the response was accompanied by resistance increase, whereas NaCl produced a depolarization, hyperpolarization or null response and the response was accompanied by resistance decrease in all cases. Most mouse taste cells showed a multiple sensitivity to four fundamental taste stimuli.
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Abstract
Intracellular recordings of mouse taste cell responses were made using glass microelectrodes filled with procion yellow dye solution. Only responses recorded from taste buds with fluorescent cells, as observed in subsequent histological preparations, were used in this study. The mouse taste cell depolarizes when stimulated with sucrose and is accompanied by either a resistance increase or no change. On the other hand, a NaCl stimulus produces a depolarization, hyperpolarization or null response and is accompanied by either a membrane resistance decrease or no change. Four sugars other than sucrose (maltose, fructose, glucose and lactose) produced the depolarization or null responses and were accompanied by an increase or no change in membrane resistance. From the above observations, it is suggested that each taste cell produces its own characteristic response profiles and membrane resistance changes for the five sugars and NaCl tested.
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Abstract
Gustatory responses from the mouse chorda tympani nerve were tested with various chemical solutions. Magnitudes of integrated chorda tympani responses to the 4 basic taste stimuli were greater in the order of HCl, sucrose, NaCl and quinine-HCl. Sucrose was the most effective sugar tested, while NaCl was the least effective salt, but divalent chloride salts were prominently effective stimulants. Many of single chorda tympani fibers responded specifically to one or two of the 4 basic taste stimuli. Single fibers sampled were classified into the following 5 types: sweet-type, Na-type, Ca-Mg-type, acid-type and quinine-type.
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Tonosaki K, Tucker D. Olfactory receptor cell responses of dog and box turtle to aliphatic n-acetates and aliphatic n-fatty acids. Behav Neural Biol 1982; 35:187-99. [PMID: 7150185 DOI: 10.1016/s0163-1047(82)91193-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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Abstract
The mitral cell odor-induced intracellular responses and the accompanying membrane resistance changes were studied in the gecko olfactory bulb. The mitral cells responded to odor either with depolarization or with hyperpolarization. The depolarization responses with hyperpolarization. The depolarization responses were accompanied by a resistance decrease. The hyperpolarization responses were accompanied by a resistance increase. The responses were enhanced by hyperpolarization and suppressed by depolarization of the membrane current. Two types of mitral cells were identified by procion yellow dye injection.
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Toyoda J, Tonosaki K. Studies on the mechanisms underlying horizontal-bipolar interaction in the carp retina. Sens Processes 1978; 2:359-65. [PMID: 225825] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Responses of on-center bipolar cells and horizontal cells were recorded simultaneously in the carp retina, and the effect of polarization of horizontal cells on the bipolar cells was studied. Hyperpolarization by extrinsic current of horizontal cells elicited in the bipolar cells a hyperpolarizing response which, unlike the electrical coupling betweeen adjacent horizontal cells, was accompanied by a change in membrane conductance. The bipolar cell responses elicited by polarization of external horizontal cells showed a negative reversal potential, while those elicited by polarization of intermediate horizontal cells showed a positive reversal potential. It was suggested that the external horizontal cells modify the cone-bipolar transmission which involves the conductance change of subsynaptic potassium and/or chloride channels, while the intermediate horizontal cells modify the rod-bipolar transmission which involves the conductance change of sodium channels.
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