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E Tabuchi

Publications and source records attributed to E Tabuchi.

25 records · Page 2Linked to original sources
PubMed1993

Neuronal responses in monkey anterior putamen during operant bar-press behavior.

Single neuron activity was recorded in the monkey anterior putamen to compare visuomotor-related responses during operant bar-press behavior with visual discrimination of objects. Of 615 neurons recorded, 9.8% (60/615) responded to the presentation of food during forced delay of access to the bar. Of these 60 neurons, 38 were also tested with nonfood, and 19 of these responded to the nonfood objects regardless of the following movement. The amplitude of the visual-related responses of some differential neurons was graded for different objects to reflect the relative degree of preference for the food presented. However, these responses disappeared in reaction time tasks in which the bar could be accessed for pressing immediately upon presentation of an object. The visual response latency of differential neurons ranged from 50 to 700 ms (mean +/- SD, 386 +/- 211 ms), which was longer than that of the nondifferential responses (207 +/- 204 ms). These results suggest that anterior putamen neurons might participate in estimation of visual information that could be related to forecasting movement.

Animals↗
PubMed1992

Hippocampal neuronal damage after transient forebrain ischemia in monkeys.

To investigate cerebral injury in the monkey due to transient ischemia, monkeys were each subjected to temporary occlusion of eight (bilateral common carotid, internal and external carotid, and vertebral) major arteries. After 0 (control), 5, 10, 13, 15, and 18 min occlusion, blood flow was restored. The monkeys were sacrificed by perfusion fixation 5 days after the operation, and all brain regions were then histologically examined for ischemic neuronal changes induced by the occlusion. The amplitude of EEG signals from skull and scalp became almost isoelectric within 1-6 min after the onset of occlusion. The EEG signals from the hippocampus were markedly attenuated within 1-4 min, although they did not become completely isoelectric. Blood pressure was significantly increased after 10-min ischemia. Five-min occlusion produced no ischemic neuronal changes except a slight increment of glial cells in the striatum and III, V, and VI layers of the neocortices. After 10- to 15-min occlusion, there were ischemic cell changes restricted exclusively to the CA1 subfield of the hippocampus. Eighteen-min occlusion produced more prominent ischemic neuronal damage in the CA1 subfield of the hippocampus, but ischemic neuronal damage was no longer confined to the hippocampus. These results suggest that only the CA1 subfield of the monkey hippocampus could be damaged by mild ischemic insult. We demonstrate that the limited lesion of the hippocampus, especially the CA1 subfield, after 10- to 15-min occlusion of eight arteries in the monkey, produces a model equivalent to human amnesia caused by transient ischemic insult.

Animals↗
PubMed1991

Amino acid and NaCl appetite, and LHA neuron responses of lysine-deficient rat.

Rats' preferences for amino acids and NaCl in their drinking behavior were noted when they were fed either a control diet of gluten plus 20% purified egg protein, or (same rats, different time) a lysine-deficient diet. In control, the order of the rats' preferences was arginine greater than saline greater than monosodium L-glutamate (MSG, umami) greater than glycine greater than water greater than threonine greater than histidine greater than lysine. When fed a lysine-deficient diet the order of preference was lysine greater than saline greater than MSG greater than glycine greater than threonine greater than water greater than arginine greater than histidine. To relate neural activity with preference for amino acids and NaCl, activity of lateral hypothalamic (LHA) neurons was recorded during ingestion of MSG, lysine, arginine, glycine, saline, glucose, or water by the control and lysine-deprived condition, following a different cue tone. When the diet was lysine deficient, some neurons responded specifically to lysine ingestion. More neurons responded nondifferentially during licking in control, and responded to lysine, but fewer to other amino acid ingestion during lysine deficiency. Responses to cue tone were associated with those during licking. The present results suggest that preference for deficient amino acids might be mediated in the LHA.

Amino Acids↗
PubMed1989

Contribution of amygdalar and lateral hypothalamic neurons to visual information processing of food and nonfood in monkey.

Visual information processing was investigated in the inferotemporal cortical (ITCx)-amygdalar (AM)-lateral hypothalamic (LHA) axis which contributes to food-nonfood discrimination. Neuronal activity was recorded from monkey AM and LHA during discrimination of sensory stimuli including sight of food or nonfood. The task had four phases: control, visual, bar press, and ingestion. Of 710 AM neurons tested, 220 (31.0%) responded during visual phase: 48 to only visual stimulation, 13 (1.9%) to visual plus oral sensory stimulation, 142 (20.0%) to multimodal stimulation and 17 (2.4%) to one affectively significant item. Of 669 LHA neurons tested, 106 (15.8%) responded in the visual phase. Of 80 visual-related neurons tested systematically, 33 (41.2%) responded selectively to the sight of any object predicting the availability of reward, and 47 (58.8%) responded nondifferentially to both food and nonfood. Many of AM neuron responses were graded according to the degree of affective significance of sensory stimuli (sensory-affective association), but responses of LHA food responsive neurons did not depend on the kind of reward indicated by the sensory stimuli (stimulus-reinforcement association). Some AM and LHA food responses were modulated by extinction or reversal. Dynamic information processing in ITCx-AM-LHA axis was investigated by reversible deficits of bilateral ITCx or AM by cooling. ITCx cooling suppressed discrimination by vision responding AM neurons (8/17). AM cooling suppressed LHA responses to food (9/22). We suggest deep AM-LHA involvement in food-nonfood discrimination based on AM sensory-affective association and LHA stimulus-reinforcement association.

Affect↗
PubMedDate not supplied

Rat preference for food-related odors.

Preferences for food-related odors and the effects of fasting on those preferences were investigated during rat bar pressing for brief odor presentation. A rat was housed in an equilateral octagonal cage and had free access to food and water, except during fasting. Among 8 food-related odor substances (black pepper, cheese, coffee, milk, nut, peppermint, plum and orange), black pepper, milk and coffee were most preferred, and cheese was least preferred, but even the bar pressing rate for cheese was above the operant level. This data indicates that all 8 odors were preferred by rats, although there were different degrees of preference in individual animals. Fasting substantially increased the rate of bar pressing for odors and changed the odors preferences. This result was probably due to increased search for food and water. Since bar pressing was reinforced by nothing other than odor presentation, the results reveal inherent odor preferences of rats.

Animals↗
PubMedDate not supplied

Calcium entry blocker ameliorates ischemic neuronal damage in monkey hippocampus.

Effects of treatment with (+/-)-1-(3,4-dimethoxyphenyl)-2-(4- diphenylmethylpiperazinyl)ethanol dihydrochloride (NC-1100), a calcium entry blocker, on ischemic neuronal damage were investigated. Monkeys were subjected to temporary occlusion of eight (bilateral common carotid, internal and external carotid, and vertebral arteries) major arteries. Blood flow was restored after 5, 10, 13, and 15 min occlusion, and NC-1100 (1 mg/kg) was then immediately infused intravenously. Monkeys were killed by perfusion fixation 5 days after occlusion. All brain regions were then histologically investigated for ischemic neuronal changes. Physiological data of NC-1100-treated subjects were not significantly different than those of untreated subjects. Heart rate tended to decrease after ischemia in treated subjects. Occlusion of 8 arteries for 10 to 15 min produced ischemic neuronal damage confined exclusively to the CA1 subfield of the hippocampus. Treatment with NC-1100 markedly reduced ischemic neuronal damage in the CA1 subfield of the hippocampus. It is suggested that postischemic treatment with the calcium entry blocker, NC-1100, might protect the brain from the ischemic damage produced in patients suffering from transient ischemia.

Animals↗