A beta-citryl-L-glutamate-hydrolysing enzyme in rat testes.

An enzyme responsible for the deacylation of beta-citryl-L-glutamate to citrate and glutamate has been characterized in rat testis. The enzyme required manganese ion for full activity and was strongly inhibited by nucleotides such as ATP or GTP. The activity was localized in the particulate fractions. The enzyme favored N-formyl-L-glutamate greater than beta-citrly-L-glutamate greater than beta-citryl-L-glutamine in a decreasing order. The amidohydrolyase activity was highest in the testis and lung, a moderate activity was detected in heart, kidney and intestine, and low in brain, thymus, stomach, skeletal muscle, spleen and liver. These findings suggest that the amidohydrolase is different from any of amidohydrolases reported so far, amidohydrolase I (EC 3.5.1.14), II (EC 3.5.1.15), III, N-acetyl-lysine deacylase (EC 3.5.1.17) and N-acetyl-beta-alanine deacetylase (EC 3.5.1.21), and various peptidases.

In vitro carboxymethylation of myelin basic protein.

During a study to find natural substrate proteins of carboxymethylation, myelin basic protein was found to be a good substrate. The two protein carboxymethylases were purified partially using myelin basic protein as a substrate. These two enzymes may be identical with protein carboxymethylase I and II, which have been found to methylate gamma-globulin. The Km of myelin basic protein (25 microM) was very small compared with other substrates. The activities of the two carboxymethylases were high in the rat brain in comparison to the other rat organs. The activity increased during the period of myelination in the rat brain. These findings suggest that carboxymethylation of myelin basic protein may play an important role in myelination.

Quantitative analysis of cholesterol in foods by gas-liquid chromatography.

In order to develop a simple and exact analytical method for cholesterol determination in foods by gas-liquid chromatography, several experiments were carried out in collaboration with several universities and institutes. For the extraction of lipids from foods, it was decided that chloroform-methanol (2:1) extraction was the most suitable procedure. Since pretreatment procedures using methods such as thin-layer chromatography and florisil column chromatography to purify the unsaponifiable matters reduced the recovery of cholesterol, and good results were obtained without applying the pretreatment, these procedures were concluded to be unnecessary. Gas chromatograms obtained with free sterol showed results similar to those of the trimethylsilyl ether derivative and acetate. 5-alpha-Cholestane is used as a good internal standard.

[Sleep-wake complaints in Parkinson's disease].

We analyzed the questionnaires concerning sleep-wake complaints in 1,575 Parkinsonian patients and 2,509 controls of 945 office workers and 1564 seniors living at home. The questionnaire included 20 contents. The Parkinsonian patients complained of sleep-wake disturbances more frequently than the controls in initiation disturbance, frequent awakenings in night, early morning awakening, day time sleepiness, usage of sleep pills, parasomnias, restless legs symptoms, nocturnal myoclonus, snoring, apnea episodes and dyspnea in night (chi-square method). The incidences of restless legs symptoms and nocturnal myoclonus increased significantly with worsening of physical symptoms in the Parkinsonian patients (p less than 0.01).

Protein carboxyl methylation in synaptic membrane of rat brain: the possible presence of adenosine-bound S-adenosyl-L-homocysteine hydrolase in the membrane.

The effects of some neurotransmitters, adenosine (Ad), and homocysteine (Hcys) on protein carboxyl methylation in synaptic plasma membranes from rat cerebral cortex were examined. Neither any of the neurotransmitters nor Ad had a detectable effect. Incubation of membrane with DL-Hcys alone (5 X 10(-5) M), the combination of both Ad (5 X 10(-5)) and DL-Hcys (5 X 10(-5)), or S-adenosyl-L-homocysteine (SAH) (1 X 10(-6)) strongly decreased the methyl ester formation. The inhibitory effect of the combination of both compounds may be interpreted in terms of the increased SAH concentration due to the presence of SAH hydrolase in the membrane. The inhibitory effect of Hcys alone was blocked by preincubation with Ad deaminase or Neplanocin A, a potent inhibitor of SAH hydrolase, suggesting the presence of Ad-bound SAH hydrolase in the synaptic membrane. Ad-bound SAH hydrolase activity estimated by the inhibition of methylation in the presence of Hcys was located in the membrane fractions including synaptosomes, myelin, and microsomes (about 70%), but the SAH hydrolase activity estimated on the basis of the inhibitory effect of the combination of both Ad and Hcys was localized exclusively in the soluble fraction (about 90%). The distribution of the latter activity is coincident with that of SAH hydrolase reported to date. Incubation of the synaptic membrane with Hcys markedly increased the SAH concentration. The stimulatory effect of Hcys alone was blocked by Ad deaminase.

Nocturnal myoclonus observed in a patient with neuroleptic-induced akathisia.

An all-night polysomnogram was twice recorded in a patient with neuroleptic-induced akathisia (NIA). The polysomnogram revealed nocturnal myoclonus. After disappearance of akathisia by the administration of clonazepam, we recorded the second polysomnogram. At the second examination, sleep efficacy increased and the total number of nocturnal myoclonus decreased remarkably. The mean inter-movement interval of nocturnal myoclonus prolonged. These findings suggest a close relationship between the mechanisms of neuroleptic-induced akathisia and nocturnal myoclonus.