Tetsuro Sakamoto

Serum folic acid levels and antipyrine clearance rates in smokers and non-smokers

Serum folic acid (FA) levels and antipyrine clearance rates were determined in 15 healthy male subjects who had not been administered any drug and alcohol for a month preceding the study. Eight of the 15 subjects smoked cigarettes daily while the remaining seven did not. The serum FA levels were measured by Lactobacillus casei bioassay. The antipyrine clearance rates were estimated in plasma or saliva obtained after oral administration of antipyrine for evaluating the activity of hepatic microsomal oxidase. The serum FA levels in the smokers were significantly lower than those in the non-smokers and the antipyrine clearance rates were significantly higher in the smokers compared with the non-smokers. The increase of the antipyrine clearance rates in the smokers was supposed to be caused by an increase in the activity of hepatic microsomal oxidase since it has been established that polycyclic aromatic hydrocarbons contained in cigarette smoke induce these enzymes. The association of the decrease in the serum FA levels and the increase of the antipyrine clearance rates was investigated.

Effects of hCRH on sleep and body temperature rhythms

Abstract We investigated the effects of human corticotropin‐releasing hormone (hCRH) on the sleep structure and body temperature rhythms of seven healthy young men. Polysomnographic recordings were obtained and body temperatures were monitored continuously for 48 h in each subject following the intravenous administration of saline or of 100 μg hCRH. The administration of hCRH was associated with a significant phase‐advancement in body temperature rhythm vs the saline control. The administration of hCRH affected non‐rapid eye movement (NREM) sleep by reducing significantly slow wave sleep (SWS) and sleep efficiency, whereas the percentage of sleep stages 1 and 2 were increased significantly. These changes in body temperature rhythms and sleep structure induced by hCRH resembled those observed in patients with endogenous depression, except for the findings during rapid eye movement (REM) sleep. We hypothesize that a hypersecretion of hCRH in patients with endogenous depression may help to explain the changes in body temperature rhythms and sleep structure often reported in such patients.

Effects of acetazolamide on the sleep apnea syndrome and its therapeutic mechanism

Abstract Twenty male patients with sleep apnea syndrome were treated with acetazolamide (AZM), a carbonic anhydrase inhibitor. In 14 of the patient a significant decrease was found in the number of apnea, apnea index and % apnea time (percentage of time spent with apnea to the total sleep time) with improvement in sleep structure, clinical symptoms, such as insomnia, daytime excessive sleepiness and snoring. A significant decrease was also observed in arterial blood pH and HCO−3 in the 14 improved patients. On the other hand, no improvement occurred in the parameters of sleep apnea and sleep with AZM in the remaining six patients. Moreover, metabolic acidosis and an improvement in arterial blood gases did not occur with AZM in the six patients.

Hypnotic action of melatonin during daytime administration and its comparison with triazolam

The present study was conducted to assess hypnotic action, effects on rectal temperature and dose dependency by daytime administration of exogenous melatonin (MLT) at 1 mg, 3 mg or 6 mg to subjects consisting of seven healthy juvenile adults. As a result, exogenous MLT significantly increased total sleep time and sleep efficiency, and MLT 6mg was observed to demonstrate hypnotic effects that were nearly equal to those of triazolam at 0.125 mg. Rectal temperature was significantly decreased at MLT 1mg and 3 mg, there were no significant differences observed in the hypothermic effects at MLT 6mg. These results indicate that exogenous MLT had dose‐dependent hypnotic action on daytime sleep, and it is possible to consider that this hypnotic action was based on a direct‐acting mechanism.

Efficacy of L-846 in patients with insomnia : Evaluation by polysomnography

Abstract The effects of L‐846, an ultra‐short‐acting pyrazolopyrimidine hypnotic, on sleep were studied in nine insomniacs and two neurotic patients with insomnia. The patients were randomly assigned to receive 5 mg (n= 6) or 10 mg (n= 5) L‐846. The study schedule comprised of one adaptation night, two baseline nights, three drug nights, and two withdrawal nights. Sleep latency and slow wave sleep (SWS) latency was largely shortened and %SWS increased in the early phase of sleep. No clear evidence of rebound insomnia was noted.

Effect of melatonin on sleep and rectal temperature of young healthy evening types

The present study assessed in healthy nocturnal juveniles the presence or absence of the hypnotic action of exogenous melatonin and its effect on core temperature by oral administration of exogenous melatonin at a pharmacologically low dose 15 min before going to bed at the normal time. Both sleep latency and the number of instances of waking up after falling asleep tended to decrease, while the amount of Stage 2 sleep increased significantly. However, no hypothermic action regarding the rectal temperature for changes in the circadian phase were observed. According to those results, it is possible that exogenous melatonin has some direct hypnotic action on habitual night sleep, although the extent of this action is considered to be relatively weak.

Folic acid in serum and cerebrospinal fluid of chronic alcoholics and methamphetamine addicts

The folic acid (FA) levels in serum and cerebrospinal fluid (CSF) of 39 chronic alcoholics, 15 methamphetamine addicts and 18 control subjects were determined using the technique of Lactobacillus casei assay. Twelve of the 39 alcoholics developed delirium tremens (DT) after determination of the FA level. The serum FA level of the alcoholics with DT was significantly lower than that of the controls, and showed a tendency to be lower than in the alcoholics without DT. The CSF FA of the DT group was significantly lower than that of the control group and of the alcoholics without DT. In the methamphetamine addicts, although the serum FA was significantly lower than that of the controls, the CSF FA remained unchanged. All the methamphetamine addicts demonstrated psychological dependence and tolerance development as did the alcoholics, but they did not show any physical dependence. From these results, a mechanism underlying the development of symptoms of physical dependence such as DT was discussed in relation to the CSF FA.

Excessive twitch movements in rapid eye movement sleep with daytime sleepiness

Abstract  A man who showed excessive twitch movement, such as fragmentary myclonus (FM) and periodic movements in sleep (PMS) predominantly during REM sleep, is reported. He complained of excessive daytime sleepiness (EDS). After examination, his twitch movements were shown not to accompany narcolepsy, and his EDS were considered to originate from nocturnal sleep disturbance caused by FM and PMS.

Insomnia in the Aged

Interview surveys (Gilleard et al., 1984; Karacan et al., 1983; McGhie and Russell, 1962; Morgan et al., 1988) of inhabitants in certain areas in foreign countries have showed an increased in the number of people who are aware of insomnia with age and frequent use of hypnotics, However in Japan, there are few such surveys.

Therapeutic progress of two sibling cases exhibiting sleep–wake rhythm disorder

In this study, two females, siblings who exhibited a non‐24 h sleep–wake rhythm (non‐24 h) at home were observed. However, they showed a delayed sleep phase syndrome (DSPS) immediately after admission to Kurume University Hospital. Melatonin (3 mg) was commenced following chronotherapy and this improved their sleep–wake rhythm. 1,2 Polysomnography (PSG) showed decreased sleep latency and increased sleep stage. 4 In these cases, the involvement of environmental factors was strongly suggested for the sleep–wake rhythm abnormalities as well as familial factors.