Epileptic seizure of El mouse initiates at the parietal cortex: depth EEG observation in freely moving condition using buffer amplifier.

The initiation site of seizure discharges and the relationship between behavioral manifestations and electroencephalography were investigated in the El mouse, a hereditary epilepsy model. The chronic depth electrodes were implanted stereotaxically into the frontal cortex, parietal cortex, temporal cortex, hippocampus, striatum, amygdaloid complex, non-specific nuclei of thalamus and substantia nigra. Electrical activities were recorded in freely moving condition with use of the buffer amplifier devised in the laboratory and behaviors were monitored simultaneously.

CNV-like potentials on the cortical surface associated with conditioning in head-restrained rats.

Head-restrained rats were conditioned to perform a CNV task: to press a lever in response to an imperative auditory stimulus (S2) given 1.5 sec after a warning stimulus (S1) for a drop of jelly food. With an electrode on the surface of the forelimb cortex, (1) sharp wave complexes immediately after S1 and S2, and (2) a negative slow potential (SP) between S1 and S2, on which early and late components were discernible, were recorded in association with performance of this task.

Ultrastructural and immunohistochemical study of degenerate neurite-bearing ghost tangles.

Some ghost tangles in the brains of Alzheimer patients were accompanied by many small argyrophilic structures which were electron microscopically confirmed to be degenerate neurites. In these ghost tangles, roughly dispersed 15 nm straight and occasional twisted tubules were penetrated by proliferated astrocytic processes. Immunohistochemically, these ghost tangles lost immunoreactivities to anti-NFT, -tau and -ubiquitin antibodies, but were thioflavine-S fluorescent, though antigenicity to beta-protein was not proved.

Characterization of a transthyretin-related amyloid fibril protein from cerebral amyloid angiopathy in type I familial amyloid polyneuropathy.

Recently, it has been reported that transthyretin (TTR)-immunoreactive amyloid deposition with cerebral amyloid angiopathy in central nervous system is a common pathological finding in type I familial amyloid polyneuropathy (FAP). In the present study, we performed isolation and sequence analysis of TTR-related amyloid fibril protein from the meninges of a patient with type I FAP. Purified major amyloid fibril protein had a molecular weight of 15 kDa.

Auditory-evoked response of the cortex after yohimbine administration: phase advance effect of central noradrenergic activation.

The effects of central noradrenergic activation on an auditory-evoked cortical response were studied using systemic administration of yohimbine (2 mg/kg intravenously, IV), a noradrenergic stimulant, in 13 anesthetized rats. To analyze changes of the response, surface and intracortical evoked potentials (EP) as well as extracellular single-unit recordings with tungsten microelectrodes were employed. It was noted that the initial-positive wave of the surface EP corresponded to unit firing responses in a restricted area of the auditory cortex, where the surface EP was largest and a polarity inversion of the intracortical EP was observed.

A comparison of alexithymia in American and Japanese dialysis patients.

A comparison of alexithymia in American and Japanese dialysis patients was performed using the Beth Israel Hospital Questionnaire (BIQ) and the MMPI Alexithymia Scale (MMPI-AS) including structured interviews. No significant differences between the USA and Japan were observed in all dialysis patients with both BIQ and MMPI-AS. However, the alexithymia score in US hemodialysis (HD) patients was significantly lower than that in Japanese HD patients, whereas the alexithymia score in American continuous ambulatory peritoneal dialysis (CAPD) patients was significantly higher than that in Japanese CAPD patients.

The influence of defense mechanisms on secondary alexithymia in hemodialysis patients.

The influence of psychodynamic aspects such as the defense mechanisms for conflict on secondary alexithymia in hemodialysis (HD) patients was examined among 35 HD patients and their family members. Although HD patients had quite strong conflicts due to HD therapy, the manifestation of conflict and expressiveness toward the family were significantly lower in HD patients with alexithymia than in those without alexithymia. Significantly positive and negative correlations were observed between conflict and expressiveness, and between expressiveness and degree of alexithymia, respectively.

Evaluation of a cholinomimetic drug, 9-amino-2,3,5,6,7,8-hexahydro-1H-cyclopenta [b] quinoline (NIK-247), as an enhancer of endogenous efflux of acetylcholine from brain slices.

Basal and high K(+)-stimulated efflux of endogenous ACh from slices of brain was measured to evaluate the cholinomimetic effect of 9-amino-2,3,5,6,7,8-hexahydro-1H-cyclopenta[b] quinoline monohydrate HCl (NIK-247) on the central nervous system. The drug NIK-247 dose-dependently accelerated the efflux of ACh from slices of striatum. The maximum increase produced by 1.

Selective loss of nigral neurons in Alzheimer's disease: a morphometric study.

Loss of neurons from the substantia nigra (SN), which is sometimes observed in Alzheimer's disease (AD), was quantitatively analyzed in 10 cases of presenile AD and 19 age-matched controls. On sections from the upper and lower portions of the SN, the pigmented zone (zona compacta) and the non-pigmented zone (zona reticulata) were delineated, and these zones were partitioned into quarters: medial, mid-medial, mid-lateral and lateral. This approach clarified topographical preference of neuronal depletion in the SN of AD; namely (1) pigmented neurons were more severely affected than non-pigmented neurons, (2) neuronal depletion was more marked in the lower SN (-38%, P less than 0.

The effects of corticotropin-releasing hormone on peptidergic neurons in the rat forebrain.

Our previous study showed that intracerebroventricular (ICV) administration of corticotropin-releasing hormone (CRH) produced a significant increase in locomotor activity at a dose of 1 microgram and slow stereotypy with prominent grooming at a dose of 10 micrograms. In addition, the ICV administration of CRH caused a significant increase in dopamine (DA) and norepinephrine turnover (NE) in various forebrain regions. The present study was designed to investigate the effects of the ICV administration of CRH on cholecystokinin (CCK), neuropeptide Y (NPY), somatostatin (SOM) and gamma-amino butyric acid (GABA) in the rat forebrain.

Mutation of Glu693 to Gln or Val717 to Ile has no effect on the processing of Alzheimer amyloid precursor protein expressed in COS-1 cells by cDNA transfection.

One of the features of Alzheimer's disease (AD) is the formation of senile plaques, of which the main component is a 42 amino acid beta-protein (beta P). Molecular cloning of beta P revealed the presence of a 90-130 kDa precursor, amyloid precursor protein (APP). Since APP is expressed in normal brain without producing beta P, some abnormal processing is the cause of the formation of beta P in AD.

Long-term potentiation of the amygdalo-striatal synaptic transmission in the course of development of amygdaloid kindling in cats.

Limbic projection from the amygdala to the basal forebrain and the neostriatum was studied physiologically during development of amygdaloid kindling in cats. Stimulation of the basolateral amygdaloid nucleus (BL) produced the negative field potential monosynaptically in the nucleus accumbens (Acb), while in the caudate nucleus (Cd) it produced a slight negative deflection with a longer latency. The latter is produced disynaptically as it showed marked facilitation in its amplitude when two stimuli were applied at short intervals.

"Secretase," Alzheimer amyloid protein precursor secreting enzyme is not sequence-specific.

The major pathological change in Alzheimer's disease is the deposition of amyloid beta/A4-protein (beta P) in the brain. beta P is derived from a small part of the much larger amyloid protein precursor (APP). In the normal condition, APP is cleaved in the interior of beta P, preventing the formation of beta P, by a hypothetical proteinase "secretase".

[A new type of complicated form of hereditary spastic paraplegia showing mental deterioration, quadriplegia with muscular atrophy, sensory disturbance, extrapyramidal disorders, and epilepsy].

Unlabelled: This study proposes a new type of complicated form of hereditary spastic paraplegia (HSP) and some problems on a clinico-pathological classification of HSP. The present study includes three male and two female patients from two families (A and B). In the family A, four siblings (two males and two females) were affected.

Determination of peptidylglycine alpha-amidating monooxygenase activity in human serum by thin-layer chromatography.

We developed a simple assay system for the quantitative evaluation of peptidylglycine alpha-amidating monooxygenase activity using as substrate a 125I-labeled synthetic tripeptide, 125I-D-Tyr-Val-Gly, thin-layer chromatography, and a radiochromatoscanner. The basic principle of this method is that thin-layer chromatography separates the reaction product, 125I-D-Tyr-Val-NH2, from the substrate in an assay mixture. The 125I activities of both substrate and product separated from each other on a thin-layer chromatography plate were quantified with a radiochromatoscanner and the rate of conversion of the substrate to the product was calculated from their counts.

A novel brain-specific mRNA encoding nuclear protein (necdin) expressed in neurally differentiated embryonal carcinoma cells.

A novel DNA sequence has been isolated from a subtraction cDNA library of P19 embryonal carcinoma cells treated with retinoic acid which induces neural differentiation of the stem cells. The cDNA insert (4B) hybridized with a single 1.7 kb mRNA, whose abundance was markedly increased in P19 cells after retinoic acid treatment.

Alzheimer amyloid beta/A4 peptide binding sites and a possible 'APP-secretase' activity associated with rat brain cortical membranes.

We carried out ligand binding experiments on membranes from rat brain cortical grey matter using radioiodinated beta/A4 8-17, with non-specific binding determined by the addition of 10 microM unlabelled peptide. Specific, reversible binding amounted to 60-75% of total binding and showed a clear dependence on time, temperature, pH and membrane concentration. Kinetic analyses indicated a high-affinity binding site with an apparent KD of 440 pM.

The effects of intraperitoneally administered phencyclidine on the central nervous system: behavioral and neurochemical studies.

The effects of intraperitoneally (IP) injected phencyclidine (phencyclohexyl piperidine; PCP) on the metabolism of dopamine (DA) and cholecystokinin-like immunoreactivity (CCK-LI) in the rat brain were investigated in connection with PCP-induced behavioral changes. The predominant behavior change elicited by 2.5 mg/kg PCP was locomotion, while with higher doses (5 and 10 mg/kg) sniffing, swaying and falling were observed in addition to the enhanced locomotor activity.

[Clinical concept of alcoholic dementia].

Intellectual deterioration, changing in behavior and affect are often seen in association with long continued and heavy alcohol ingestion and such deteriorated states of patients are called alcoholic dementia. A large number of investigators have attempted to designate clinical concept of alcoholic dementia throughout the centuries and many kinds of term like as alcoholic pseudo-paralysis, alcoholic mental deficiency and alcoholic deterioration, etc, have been submitted since the beginning of 19th century. Numerous psychometric studies have indicated cognitive impairment and memory disturbance in chronic alcohol abusers and moreover brain PEG and CT-scan studies have shown sulcal widening and enlarged ventricles to be common in alcoholics.

[Aspects of psychologic disorders in Japanese students].

The present study discusses the reasons which moved 88 students during one year from April 1987 till March 1988 to make their first spontaneous visit to the Department of Psychiatry in the Health Service Center of Tokyo University. The number of patients amounted to 0.60% of the total student enrollment during the period mentioned.

Striatopallidonigral degeneration in Pick's disease: a clinicopathological study of 41 cases.

The frequency and degree of stiatopallidonigral (SPN) degeneration were examined in 41 autopsy cases of Pick's disease. Based on the degree of SPN degeneration, these cases were arranged into four groups: 1) group I (severely degenerate; 19.5%), 2) group II (moderately degenerate; 22.

The levels of urinary epinephrine during daytime REM sleep deprivation.

Urinary excretion of epinephrine during REM sleep deprivation in the daytime was examined in an attempt to determine whether epinephrine excretion during sleep is related to the structure of disturbed sleep. Six healthy males were subjected to two experimental conditions: 1) day sleep without interruption, as a control condition, and 2) day sleep with REM sleep deprivation. Under both conditions, epinephrine excretion levels of five of the subjects were found to be distributed along a basal regression line, expressing the relationship of epinephrine excretion and percent of waking time, as calculated in a previous study.