Changes in single unit activity in the lateral hypothalamic area of goats during feeding.

In order to clarify the location of feeding centers in the ruminant brain, this study used a single-unit activity (SUA) recording electrode to investigate the existence of appetite-regulating neurons in the lateral hypothalamic area (LHA) in goats. Seven male Japanese Saanen goats were used in the experiment. The animals were fed twice daily, once in the morning (1000 to 1200) with 1.5 kg of roughly crushed alfalfa hay cubes, and once in the afternoon (1600 to 1800) with 200 g of commercial ground concentrate feed. The animals were allowed free access to drinking water. In this study, the animals were surgically operated on to position the recording electrode in the LHA. Recordings of SUA were carried out continuously over a 2.25-h period beginning 15 min prior to the commencement of morning feeding. The eating rates of crushed alfalfa hay cubes were highest 10 min after feeding commencement, but decreased sharply by the time 40 min had elapsed. The cumulative feed intake after the completion of the 2-h feeding period was 1164 +/- 38 g. The cumulative water intake upon the conclusion of the 2-h feeding period was 2422 +/- 107 mL. This study recorded 31 units, of which five showed a response to feeding and altered their firing rates. In response to a sharp increase in eating rates, all five units increased their firing rates to a level higher than that of prefeeding (P < 0.05). As the animals reached a level of satiety (eating rates declined to very low levels), firing of units I and II stopped completely, while the firing rates of units III, IV, and V decreased. Examination of a serial histological section confirmed that the five units in which changes in firing rates with feeding were observed were all located in the dorsolateral hypothalamic area close to the fornix. The LHA neurons recorded in this experiment characteristically showed neuronal activity increases at high levels of feeding, but decreases at low levels. The results suggest that there are cells located in the LHA of goats that are active in the physiological regulation of hay (dry forage) intake.

Platelet serotonin concentrations in medicated schizophrenic patients.

1. The present study was conducted to investigate the effects of neuroleptic administration on platelet serotonin (5-HT) levels, and the relationships between platelet 5-HT levels, extrapyramidal symptoms (EPS) and psychopathology in schizophrenia. 2. The subjects were 49 regularly medicated inpatients who were diagnosed according to the DSM-IV criteria for schizophrenia. Each patient gave informed consent for the research involved in this study. All patients were first considered as one group and then divided into two groups: those with lower levels (LL) and those with higher levels (HL), according to their platelet 5-HT levels. Psychotic symptoms and EPS were assessed using the Brief Psychiatric Rating Scale and the Drug Induced Extra-Pyramidal Symptoms Scale, respectively. 3. (1) The mean level of the platelet 5-HT in the schizophrenics with neuroleptic-treatment was significantly lower than that in the normal subjects. (2) The mean level of the blood monoamine oxidase (MAO) in the schizophrenics tended to be lower than that in the normal subjects. (3) There was no significant difference in the mean scores of the positive symptoms, negative symptoms, or EPS between the LL and HL groups. (4) Platelet 5-HT levels were not correlated with blood MAO concentrations. 4. Overall, these results seem to indicate that (i) administration of neuroleptics lowers platelet 5-HT levels, and (ii) platelet 5-HT levels in the schizophrenics with neuroleptic-treatment do not reflect psychopathology of schizophrenia or severity of neuroleptic-induced EPS.

Sexual intercourse as a precipitating factor of transient global amnesia.

A Japanese female case of transient global amnesia (TGA), who developed an amnesic episode after sexual intercourse, is reported. The mechanism of how TGA in the present case is precipitated by sexual intercourse could be explained by the elevated blood pressure during sexual intercourse that drops rapidly, causing a temporal ischemia in the distribution of the basilar artery. Furthermore, the importance of sexual intercourse as a precipitating factor of TGA is stressed.

Evoked potentials of self-interrupted Jacksonian epilepsy.

We describe a female case of Jacksonian epilepsy who can interrupt the spreading of her march by grasping her fingers firmly with her right hand. Neurophysiologically, Somatosensory evoked potential (SEP) was remarkably decreased in amplitude with pressure stimulation similar to her method. Such a change in SEP was observed also in a healthy subject. Accordingly, it is suggested that the stimulation only to the proprioceptor of fascia suppresses the activity in the cortex.

Electroencephalographic changes during and after water intoxication.

A case of water intoxication with remarkable hyponatremia was investigated with a special reference to EEG changes during and after the episode. The patient recovered his EEG as his consciousness disturbance had improved through an intravenous infusion of high osmolality saline, correlating with the serum sodium level. Further, the clinical importance of recording EEG for water intoxication was stressed.

The complex episode of transient global amnesia.

In most reports, Transient Global Amnesia (TGA) consisted of a single episode of total amnesia. The detailed investigation on the process of recovery from amnesia in the present two cases of TGA indicated the existence of a complex episode of TGA which consisted of a sequence of episodes of total amnesia.