Masuyuki Namba

Decreased level of β-endorphin-like immunoreactivity in cerebrospinal fluid of patients with senile dementia of Alzheimer type

β-Endorphin-like immunoreactivity in cerebrospinal fluid (CSF) was observed to decrease in patients with Huntingtons disease and dementia due to brain vascular disease. The greatest decrease was seen in patients with presenile and senile dementia of Alzheimer type (SDAT). The immunoreactivity significantly correlated with psychological functions when examined using a dementia rating scale (r = 0.51, p < 0.01, for all dementia, r = 0.65, p < 0.02, for only SDAT). These results suggest that a B-endorphin-like substance may be related in the pathophysiology of dementia.

Idiopathic parkinsonism with lewy-type inclusions in cerebral cortex. A case report

SummaryA case of idiopathic parkinsonism showed specific neuropathological findings, namely, the diffuse appearnces of intracytoplasmic inclusions of Lewytype in the cerebral cortex in addition to many Lewy bodies in the pigmented brain stem nuclei. The staining properties and the ultrastructure of the inclusions in the cerebral cortex had a strong resemblance to those of the Lewy bodies in the substantia nigra, though a few electron microscopical differences were observed. Almost all of these ‘cortical inclusions’ were homogeneous or had an obscure core in their center, and they gave the impression of immature Lewy bodies.

Plasma glutamate decarboxylase activity in neuropsychiatry

Plasma glutamate decarboxylase (GAD) activity was measured in patients with endogenous psychoses and neurologic diseases. Unmedicated schizophrenic patients showed no difference in plasma GAD levels compared to controls. Administration of neuroleptics together with anticholinergic agents increased plasma GAD activity in schizophrenic patients. Compared to controls, patients with major depression and bipolar illness showed significantly lower GAD activity. No effect of antidepressants and minor tranquilizers on plasma GAD activity was found. Relatively lower GAD activity was shown in neurotic patients. The enzyme activity in plasma of patients with Huntingtons chorea (HC) was lower than control levels. The plasma GAD concentrations correlated with cerebrospinal fluid concentrations in five HC patients.

Platelet aggregation response in schizophrenia and prostaglandin E1.

Platelet aggregation response to various stimulants was examined in 18 unmedicated schizophrenic patients, 13 medicated patients, and 13 control subjects. Platelet aggregation response to epinephrine decreased only in unmedicated schizophrenic patients. Clinical improvement in seven patients after neuroleptic medication was significantly correlated with an increase in platelet aggregation response to arachidonic acid, and nonsignificantly to epinephrine, dopamine, and serotonin. The inhibitory effect of prostaglandin E1 on platelet aggregation response to adenosine diphosphate was investigated in seven unmedicated schizophrenic patients, six medicated patients, and eight controls. The inhibitory effect of prostaglandin E1 on platelet aggregation response to adenosine diphosphate was significantly reduced in all unmedicated schizophrenic patients. Neuroleptic medication had some effect in normalizing aberrant sensitivity to prostaglandin E1 in those patients, although acute medication induced an adverse reaction in the controls.

Ultrastructure of acetylcholinesterase synthesizing neurons in the neostriatum

Acetylcholinesterase (AChE) ultracytochemistry with thiocholine method was studied in the rat neostriatum. AChE synthesizing neurons were identified by observing reappearance of the enzyme after application of an AChE inhibitor, DFP. Neurons in the neostriatum were classified into 6 types. All such types were demonstrated to synthesize AChE. Two types of efferent neuron (types III and IV) have shown a relatively large amount of AChE and resynthesized the enzyme in the earlier stage after DFP. A tentative model of the neuronal network in the neostriatum was schematically shown.

Two types of dopaminergic nerve terminals in the rat neostriatum. An ultrastructural study

In the neostriatum 7.7% of all boutons absorbed alpha-methylnoradrenaline, thus staining their synaptic vesicles profiles granular. These presumably monoaminergic synapses were divided into two types according to ultrastructural features. Type A was composed of a relatively large axon terminal and a dendritic spine with postsynaptic membrane thickening. The axon terminal of type B, that is a bouton en passant, was smaller than the postsynaptic profile, while the synaptic contact was symmetrical. Following nigral coagulation, both types of synapse degenerated. It is concluded that both types of synapse are dopaminergic.

Creutzfeldt-jakob disease — alteration in ganglioside sphingosine in the brain of a patient

Gangliosides isolated from the brain of patients with Creutzfelt-Jakob (C-J) disease were analyzed. The ganglioside current was abnormally low, and the percentage distributions of individual gangliosides and the long-chain base compositions were abnormal. The C20-sphingosine contents of all the ganglioside fractions were low. Abnormalities in ganglioside long-chain bases in adult human brain have been reported previously only in patients with inherited metabolic disorders. These abnormalities in C-J disease seem to be closely related to the cause of the disease.

Abnormal Phosphatidylinositol‐Cycle of Platelet Membrane in Schizophrenia–––A Preliminary Study

Abstract: Phosphatidylinositol (PI)‐cycle in the platelet membrane was examined in eight untreated patients with psychotic symptoms. A defect of PI‐cycle in the transformation from 1,2–diacylglycerol into phosphatidic acid was found in three patients, who were diagnosed as having Schizophrenic Disorders or Schizophreniform Disorder according to the DSM‐III criteria. Two out of the three patients were reexamined while undergoing neuroleptic medication, and they showed the same abnormality in PI‐cycle. Further studies were required to determine the nature of the abnormality in PI‐cycle in the platelets of schizophrenics.

Substance P-like immunoreactivity in plasma of psychotic patients and effects of neuroleptics and electroconvulsive therapy

Radioimmunoassay of substance P (SP)-like reactivity, using N alpha-tyrosyl-SP, was performed in plasma of psychotic patients. Schizophrenic patients under neuroleptic medication over 1 year, and those patients with organic brain disease showed a significant increase in immunoreactivity. The immunoreactivity in unmedicated schizophrenic patients just before treatment and in depressed patients, both bipolar and major, did not differ significantly from that of controls. The immunoreactivity in unmedicated schizophrenics was followed after medication for a maximum of 5 months. The reactivity decreased in five cases, and increased in three cases. No definite pattern could be discerned between changes in the immunoreactivity, the type of medication administered, and the resultant response to the therapy. Chlorpromazine injection caused no definite acute effect on the plasma level of SP-like immunoreactivity for 120 minutes. Electroconvulsive therapy increased the plasma level of SP-like immunoreactivity for 90 minutes in a male schizophrenic patient.

Ultracytochemical observations of choline acetyltransferase neurons in the rat neostriatum.

SummaryThe fine structural localization of ChAc activity was studied in the rat neostriatum by a ultracytochemical method. The reaction products of ChAc activity were seen in the cisternal structures and plasma membrane of some medium-sized neurons. Some boutons with ChAc-positive vesicles were observed to make an axo-dendritic or axo-somatic symmetrical synapse.