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Yoshio Morita

Publications and source records attributed to Yoshio Morita.

17 recordsLinked to original sources
PubMed2006

Lobeline attenuates methamphetamine-induced stereotypy in adolescent mice.

In this study, we investigated the effects of lobeline, an alkaloid constituent of Indian tobacco, on methamphetamine (METH)-induced stereotypy in male ICR mice (41-50 days old), an animal model for amphetamine psychosis. After a single administration of METH (10 mg/kg, i.p.), mice showed an initial short-lasting hyperlocomotion and subsequent stereotyped behaviors with a plateau level 25 min after drug challenge. Pretreatment with lobeline (3.0-30 mg/kg, i.p.) 15 min prior to the drug challenge significantly decreased the intensity of stereotypy and increased its latency to onset in a dose-dependent manner, especially 20 min after the drug challenge. In saline challenge groups, the doses of lobeline examined did not affect spontaneous locomotion nor induced any stereotyped behaviors. High-performance liquid chromatography analysis revealed that the range of lobeline doses examined except 30 mg/kg did not affect apparent monoamine turnover in the cerebral cortex, the region of the striatum and nucleus accumbens, and the region of the thalamus and hypothalamus of the mice 20 and 60 min after the drug challenge. These results suggested that the inhibitory effect of lobeline (3.0-10 mg/kg) on METH-induced stereotypy was not attributed to the change in the apparent monoamine turnover.

Animals↗
PubMed2006

IL-18 mediates the formation of stress-induced, histamine-dependent gastric lesions.

A role of IL-18 in the induction of gastric lesions by water immersion and restraint stress (WRS) was investigated. When wild-type BALB/c mice were exposed to WRS, levels of IL-18 in the serum and stomach increased rapidly with the development of acute gastric lesions. In IL-18-deficient mice [IL-18 knockout (KO) mice] similarly exposed to WRS, no gastric lesions were observed, but the administration of IL-18 before exposure to WRS resulted in the induction of WRS-induced gastric lesions. WRS enhanced gastric histidine decarboxylase (HDC) activity with concomitant increases in gastric histamine content. In IL-18 KO mice, the WRS-induced elevation of gastric HDC activity and histamine levels was much less than that in wild-type mice, but it was augmented by prior administration of IL-18. Treatment of wild-type mice with cimetidine, a histamine H2 receptor antagonist, inhibited the formation of WRS-induced gastric lesions with no effect on the induction of gastric IL-18 by WRS. Levels of corticosterone, one of the stress indicators, were lower in IL-18 KO mice than in wild-type mice. The glucocorticoid receptor antagonist mifepristone had no effect on gastric IL-18 and histamine levels but aggravated the stress-induced gastric lesions, indicating that corticosterone was not involved in the IL-18-mediated formation of stress-induced gastric lesions. These results indicate that IL-18 is involved in the induction of gastric lesions by WRS through augmentation of HDC activity and production of histamine in the stomach.

Animals↗
PubMed2006

Methamphetamine reward in mice as assessed by conditioned place preference test with Supermex sensors: effect of subchronic clorgyline pretreatment.

Recent studies in our laboratory have shown that methamphetamine (METH)-induced hyperlocomotion and behavioral sensitization in mice were inhibited by clorgyline, an irreversible monoamine oxidase inhibitor. In this study, the effect of clorgyline pretreatment on METH-induced rewarding effect was assessed by a conditioned place preference (CPP) test, using an apparatus developed with Supermex sensors (infrared pyroelectric sensors). Although intact male ICR mice showed significant CPP for METH (0.5 mg/kg, i.p.), pretreatment with subchronic clorgyline (0.1 and 10 mg/kg, s.c.) did not affect the magnitude of CPP. At a dose of 1 mg/kg, pretreatment of the mice with clorgyline showed a similar CPP index in both saline/saline and METH/saline pairing groups. During the conditioning session, the mice did not express behavioral sensitization to METH. Pretreatment with clorgyline (0.1, 1, and 10 mg/kg) decreased striatal apparent monoamine turnover in a dose-dependent manner. These results indicated that clorgyline pretreatment (0.1 and 10 mg/kg) did not influence the METH-induced rewarding effect in mice, although pretreatment of the mice with clorgyline at a dose of 1 mg/kg appeared to influence the CPP for METH.

Analysis of Variance↗
PubMed2006

Prepulse inhibition of acoustic startle response in mild cognitive impairment and mild dementia of Alzheimer type.

Amnestic mild cognitive impairment (MCI) describes the condition of memory-impaired individuals who otherwise function well and do not meet the clinical criteria for dementia. Such individuals are considered to represent a transitional stage between normal aging and dementia of Alzheimer type (DAT). Neurobiologic changes in amnestic MCI, and their significance for psychophysiologic function, are poorly understood. In this study, the authors compared acoustic prepulse inhibition (PPI) between subjects with amnestic MCI and mild DAT to characterize sensorimotor gating. The acoustic startle reflex, which the authors measured using an accelerometer and electromyogram, involves whole-body movement and eye blink in response to a sudden loud noise (115 dB). PPI is inhibition of this reflex by a softer noise (prepulse; 85 dB) preceding the startle stimulus by 30 ms. PPI was examined in 30 controls, 20 subjects with amnestic MCI, and 20 subjects with mild DAT. Neither amnestic MCI nor mild DAT affected startle movement amplitude. Subjects with amnestic MCI showed significantly enhanced PPI (gating facilitation), while subjects with mild DAT exhibited significantly less PPI than controls (gating deficit). This pattern of PPI changes suggests that neuropathologic changes in the limbic cortex, mainly the entorhinal cortex, at the earliest stage of DAT might be responsible for PPI abnormalities via disturbed regulation of the limbic cortico-striato-pallido-pontine circuitry. Startle PPI changes could be used as a biologic marker for amnestic MCI and mild DAT.

Acoustic Stimulation↗
PubMed2006

[Case with probable dementia with Lewy bodies, who shows reduplicative paramnesia and Capgras syndrome].

We report a case of probable dementia with Lewy bodies (DLB), showing reduplicative paramnesia (RP) and Capgras syndrome (CS). The patient, a right-handed 60 year-old male, began to show progressive dementia. At the age of 65, he showed fluctuating cognitive impairment and recurrent visual hallucinations. His SPECT demonstrated hypoperfusion not in the medial temporal cortices, but in the parieto-occipital lobes, where the right hemisphere was dominantly hypoperfused. He was diagnosed with probable DLB. In addition to recurrent visual hallucinations, he showed a sense of self- (or others) transfiguration, consciousness of something non-existent (Leibhaftige Bewusstheit; Jaspers, K.), and fluctuating visuo-spacial impairment. At the age of 67, he gradually complained of his duplicative wives "sosie". Finally he went so far as to talk about a nameless phantom boarder. We considered that RP and CS of this case comprised a sense of self-(or others) transfiguration, misidentification of important persons and places, and productive symptoms such as consciousness of something non-existent (Leibhaftige Bewusstheit) and visual hallucinations. The above mentioned symptoms might be originated not only from the disturbance of visuospacial recognition, which involves the limbic system (especially amygdala), medial frontal cortex, and right hemisphere of the brain, but also from the disturbance of recursive consciousness, due to diffusely damaged brain regions with Lewy body pathology. (Authors' abstract)

Aged↗
PubMed2005

Effects of monoamine oxidase inhibitors on methamphetamine-induced stereotypy in mice and rats.

In male ICR mice, a single intraperitoneal administration of methamphetamine (METH) (10 mg/kg) induced stereotyped behavior such as continuous sniffing, circling, and nail biting, reaching a plateau level 20 min after the injection. Subcutaneous pretreatment with clorgyline, a monoamine oxidase (MAO)-A inhibitor, at a dose of 0.1 mg/kg 2 h prior to the drug challenge significantly decreased the initial (first 20 min) intensity of stereotypies and increased the latency to onset. The effect was not observed with either higher doses of clorgyline (1 and 10 mg/kg) or l-deprenyl, a MAO-B inhibitor, at doses of 0.1-10 mg/kg. In male Wistar rats, the inhibitory effect of clorgyline on METH-induced stereotypy was not observed. Pretreatment of the mice with clorgyline (0.1 mg/kg) had no effect on apparent serotonin and dopamine turnover in the striatum, although the higher doses of clorgyline (1 and 10 mg/kg) significantly decreased the turnover. These results suggest that a low dose of clorgyline tends to increase the latency and decrease the intensity of stereotypies induced by METH in a dopamine metabolism-independent manner in mice.

Animals↗
PubMed2004

Involvement of nucleus accumbens dopaminergic transmission in acoustic startle: observations concerning prepulse inhibition in rats with entorhinal cortex lesions.

The relationship between the entorhinal cortex and prepulse inhibition (PPI) as well as the nucleus accumbens dopaminergic participation in acoustic startle were examined in rats. After the entorhinal cortex was damaged bilaterally using ibotenic acid, a microdialysis probe was placed in the nucleus accumbens for detection of dopamine before, during and after acoustic startle stimuli. In rats with bilateral entorhinal cortex lesions PPI was reduced, and extracellular dopamine in the nucleus accumbens was elevated with or without acoustic stimuli. The entorhinal cortex and the sensorimotor gating system thus may be related via dopaminergic connections in the nucleus accumbens, even though dopamine release did not coincide completely with acoustic startle stimuli.

Animals↗
PubMed2004

[A study of the effect of donepezil hydrochloride on cognitive function in patients with dementia of Alzheimer's type using WAIS-R].

The present study aimed to assess the initial effects of donepezil hydrochloride (DPZ) on various aspects of cognitive function in patients with dementia of Alzheimer's type (DAT) using the Japanese version of the Wechsler Adult Intelligence Scale-Revised (WAIS-R). DPZ was administered to 47 patients with mild-to-moderate DAT (D group). The control group comprised 61 patients who had been followed up before DPZ was released for use (C group). Both groups underwent WAIS-R testing, before and after 10 months of treatment with DPZ for group D, and at time of diagnosis of DAT and 10 months later for group C. D and C groups did not differ significantly in terms of gender ratio, years of education, age at onset of DAT, age at administration of DPZ or at diagnosis of DAT, severity of dementia, MMSE score, presence of behavioral and psychological symptoms of dementia, concomitant use of psychotropic medication, or initiation of rehabilitation. No significant differences were found between D and C groups in verbal (V), performance (P) or full-scale (F) intelligence quotient (IQ), or in six verbal subtest scores of VIQ and five performance subtest scores of PIQ on WAIS-R, before administration of DPZ or at diagnosis of DAT. For differences between each score on WAIS-R at diagnosis of DAT or before administration of DPZ and 10 months later, DPZ inhibited decreases in FIQ and in VIQ, PIQ, vocabulary, similarities, picture arrangement and object assembly subtest scores on WAIS-R. These indices are related to concept formation and abstract thinking, which form part of executive function. DPZ effectively prevented decline of cognitive function, particularly executive function, in patients with DAT.

Aged↗
PubMed2004

[Alterations of symptoms with borderline personality disorder after fronto-temporal traumatic brain injury. A case study].

We report a case of borderline personality disorder in which severe self-mutilation, sense of futility and tendency to manipulate others disappeared after fronto (orbital cortex and dorso-lateral surface) temporal traumatic brain injury. The patient, a right-handed 34 year-old woman began having severe depressive moods, irritability, and performed recurrent self-mutilation by wrist cutting after her marriage at age 20. She was diagnosed as having borderline personality disorder. At the age of 30, she attempted to kill herself by leaping from a building, and sustained a frontotemporal traumatic brain injury. After 5 years of follow-up, she recovered from Wernicke's-like aphasia, but could not understand anything complex. She also showed disturbances of writing, calculating, attention, working memory, recent and remote memories, motivation, and sense of self. The results of tests of higher brain function were as follows: Wisconsin card sorting test (Keio version), C = 1, D = 2, P = 23; FAB (Frontal Assessment Battery) = 7/18; Trail making test B = impossible. Brain MRI demonstrated left frontal lobe (orbital cortex and dorso-lateral surface) contusions, severe atrophy in the left temporal cortex including the hippocampus and amygdala, and diffuse axonal injury in the left frontal white matter. Although her recurrent self-mutilation had disappeared after brain injury, a certain type of anxiety, which occasionally induced irritability, unstable moods and devaluation of others, occurred without any trigger once or twice a month. This anxiety continued two or three days and faded away within a week. Because of its frequency and duration, this anxiety can be considered to originate not from the traumatic brain injury, but from her intrinsic nature, and seems to be parallel to annihilation anxiety (Reich A, Klein M) and abandonment anxiety (DSM-IV). Because she showed this anxiety after a severe higher brain dysfunction including disturbances of language, attention, working memory, recent and remote memories, motivation, and sense of self, we considered this anxiety to be an unarticulated form of annihilation anxiety and abandonment anxiety.

Adult↗
PubMed2003

Features of obsessive-compulsive disorder in patients primarily diagnosed with schizophrenia.

We investigated the prevalence of obsessive-compulsive disorder (OCD) among patients who were primarily diagnosed with schizophrenia. We investigated the differences in the neuropsychiatric features and motor symptoms between patients with schizophrenia who did or did not have OCD. Seventy-one subjects with the DSM-IV diagnosis of schizophrenia were evaluated by the Structured Clinical Interview for DSM-IV Axis I Disorders, the Yale-Brown Obsessive-compulsive Scale and the Positive and Negative Syndrome Scale. To assess their motor symptoms, the Abnormal Involuntary Movements Scale, the Barnes rating scale for drug-induced akathisia and the Simpson and Angus extrapyramidal symptoms (EPS) rating scale were used. The 13 subjects with OCD (18.3%) had significantly more severe motor symptoms than the non-OCD subjects. Patients with schizophrenia who exhibit moderate to severe motor symptoms as side-effects of neuroleptics, should be examined for OCD comorbidity. Patients who are found to have OCD comorbidity must be treated with carefully chosen medications, including serotonin re-uptake inhibitors.

Adult↗
PubMed2002

Reduced prepulse inhibition in rats with entorhinal cortex lesions.

The relationship between the entorhinal cortex and prepulse inhibition (PPI) as well as dopaminergic participation in this relationship were examined. PPI is an operational measure of sensorimotor gating in which a robust response to a startling auditory pulse stimulus is inhibited when the stimulus is preceded by a weak prepulse. PPI can be measured in various species and is reduced in several neuropsychiatric disorders and in dopamine-activated rats. The entorhinal cortex was damaged bilaterally using ibotenic acid, and acoustic startle experiments were performed during treatment with haloperidol or saline on day 21 after the ibotenic acid injection. Neither this injection nor haloperidol affected the amplitude of the startle movement. Bilateral entorhinal cortex lesions reduced PPI, while haloperidol partially restored it. The entorhinal cortex and the sensorimotor gating system therefore may be related via dopaminergic circuits, possibly including the nucleus accumbens. Further, as the entorhinal cortex provides the major extrinsic synaptic input to the rat hippocampus, disease involvement of this region may severely affect cognition in various disorders including schizophrenia.

Acoustic Stimulation↗
PubMed2002

Circulating nuclear matrix protein in Graves' disease.

The Fas/Fas ligand system induces apoptosis, while soluble Fas (sFas) blocks the system and soluble Fas ligand (sFasL) functions to induce apoptosis. The assay of nuclear matrix protein (NMP) released from dead or dying cells can be used to quantitate cell death. Therefore, we evaluated the relationship among serum levels of NMP, sFas, and sFasL in patients with Graves' disease. We measured serum levels of sFas, sFasL, NMP, thyroid hormones and TSH receptor antibody in 20 normal control subjects (5 men, 15 women; mean age, 44.3 years), 32 patients with untreated Graves' disease (4 men, 28 women; mean age, 44.1 years), and 10 patients with Graves' disease treated by methimazole (3 men, 7 women; mean age 39.2 years). Serum NMP was significantly lower (10.4 +/- 4.3 IU/ml, p < 0.02) in patients with untreated Graves' disease than in patients with treated Graves' disease (16.4 +/- 7.3 IU/ml) and control subjects (15.3 +/- 8.9 IU/ml). Serum sFas and sFasL were significantly higher in patients with untreated Graves' disease than in patients with treated Graves' disease and in control subjects. In the patient groups with Graves' disease, serum NMP was negatively correlated with sFas (r = -0.612, p < 0.001) and serum sFas was positively correlated with FT4 (r = 0.360, p < 0.05) and TRAb (r = 0.384, p < 0.05). Serum NMP was correlated with sFas. These results suggest that serum NMP is decreased in patients with untreated Graves' disease, and that cell death or apoptosis in patients with Graves' disease is affected by soluble Fas under the influence of thyroid function.

Adult↗
PubMed2002

[A case of intra-axial multiple cavernous angiomas, presented with dementia and cerebellar signs].

We reported a case of intra-axial multiple cavernous angiomas, presented with dementia and cerebellar signs. The patient, a right-handed 73-year-old woman, showed gait disturbances, tremor increased while writing and hypoactivity at the age of 71. Treatment with 1-dopa was not effective. At the age of 73, she was diagnosed as having intra-axial multiple cavernous angiomas on the gradient echo MRI study, which demonstrated large numbers of small low density areas (small dots) in the cerebellar cortex and moderate numbers of those in the cerebral cortices. Those small dots were not detected in the basal ganglia, the brain stem, and increased the thalamus. She clinically showed cerebellar signs, such as dysmetria, adiadochokinesia, and tremor worsening in the course of writings, in additions to the constructural apraxia, disturbances of writing, and severe perseverations. Those symptoms slightly fluctuated. However, she did not show any character changes. The results of Wisconsin card sorting test and Trial making test A were different from those usually seen in dementia with multiple infarctions in the cerebral white matters and basal ganglia. Although her cerebellar signs are considered to be due to numerous small dots in the cerebellar cortex, her parietal symptoms could not be understood by slight parietal changes such as hypoperfusions of SPECT, cerebral small dots, and infarctions in the white matters. We speculated that, by interactions between the cerebellar dysfunctions and slight parietal dysfunctions, she developed the parietal symptoms described above, which differed from dementia or Parkinsonism due to multiple cerebral infarctions, and which were characterized by slight fluctuations and alleviations with habituation.

Aged↗
PubMedDate not supplied

Plasma interleukin-18 levels in patients with psychiatric disorders.

There are an increasing number of reports on an association between the alteration of circulating cytokine levels and pathophysiology of psychiatric disorders. Plasma concentrations of interleukin (IL)-18 were measured in 13 nonmedicated patients with psychiatric disorders. There was a significant elevation of IL-18 levels in patients with major depression (n = 8) and panic disorder (n = 5), compared with normal controls. The mean IL-18 value of our psychiatric patients was comparable with that of various somatic disorders reported. We suggest that the elevation of plasma IL-18 levels reflects the increased production and release of IL-18 in the central nervous system under stressful settings. We propose that the measurement of IL-18 plasma levels may provide a useful index for the involvement of immune system in psychiatric disorders.

Adult↗