Regional and strain variation in brain 3′∶5′ cyclic adenosine monophosphate of inbred mice

Summary Regional variations were found in cAMP levels in flash frozen mouse brains with the pons and cerebellum having higher levels than the cerebrum. There were also strain variations with CBA/J and BALB/cJ having higher levels than C57B1/6J in the pons and cerebellum.     

Regional and strain variation in brain 3':5' cyclic adenosine monophosphate of inbred mice.

Regional variations were found in cAMP levels in flash frozen mouse brains with the pons and cerebellum having higher levels than the cerebrum. There were also strain variations with CBA/J and BALB/cJ having higher levels than C57B1/6J in the pons and cerebellum.     

Differential distribution of TASK-1, TASK-2 and TASK-3 immunoreactivities in the rat and human cerebellum

In this work, the distributions of some acid-sensitive two-pore-domain K⁺ channels (TASK-1, TASK-2 and TASK-3) were investigated in the rat and human cerebellum. Astrocytes situated in rat cerebellar tissue sections were positive for TASK-2 channels. Purkinje cells were strongly stained and granule cells and astrocytes were moderately positive for TASK-3. Astrocytes isolated from the hippocampus, cerebellum and cochlear nucleus expressed TASK channels in a primary tissue culture. Our results suggest that TASK channel expression may be significant in the endoplasmic reticulum of the astrocytes. The human cerebellum showed weak TASK-2 immunolabelling. The pia mater, astrocytes, Purkinje and granule cells demonstrated strong TASK-1 and TASK-3 positivities. The TASK-3 labelling was stronger in general, but it was particularly intense in the Purkinje cells and pia mater.Received 25 February 2004; received after revision 19 April 2004; accepted 28 April 2004     

Röntgenbestrahlung und Hypothermie. Der Einfluss auf Körpergewicht,Hirngewicht, Kleinhirnentwicklung und Blutbild bei neugeborenen Hausmäusen

Summary New-born mice were X-rayed under extreme hypothermia in order to estimate the radioprotective effect of hypothermia on body weight, brain weight, development of cerebellum and the hematopoietic system. A protective effect was found in the rate of survival, in body and brain weight, in the cerebellum and in the number of erythrocytes. After hypothermia, the repair of damage in the cerebellum and the erythropoietic system starts earlier. The protected mature cerebellum shows an approximately normal status. Hypothermia does not prevent the initial decrease of lymphocytes caused by X-rays, and it produces a severe disturbance of hemoglobin content.     

Pentalaminar specialized membrane junctions - tight junctions - are described in the granular layer of the pigeon cerebellum. The presence of these axo-dendritique and dendrosomatic contacts suggest the existence of electrotonic coupling in the pigeon cerebellum.

Pentalaminar specialized membrane junctions - tight junctions - are described in the granular layer of the pigeon cerebellum. The presence of these axo-dendritique and dendrosomatic contacts suggest the existence of electrotonic coupling in the pigeon cerebellum.     

Effect of cortisone or triiodothyronine administration to pregnant rats on lysosomal hydrolases in fetal forebrain and cerebellum

Triiodothyronine injected daily to pregnant rats for the last week of gestation (50 microgram/100 g b.wt) increased the specific activities of 5 acid glycosidases in the fetal forebrain and cerebellum. Cortisone (50 mg/100 g b.wt) administered in the same period had no effect on cerebellum acid hydrolases, but decreased their activity in the forebrain.     

Altered brain cholinergic enzymes activity in the genetically obese rat

Genetically obese male Zucker rats (fa/fa) and their lean littermates (Fa/-) were used in this experiment. Fourteen-week-old obese and lean littermates were sacrificed and choline acetyltransferase (ChAT) and acetylcholinesterase (AChE) enzymes were assayed in specific brain regions. The assays of these enzymes indicate that obese animals had a significantly lower ChAT activity in the cerebellum, pons, and cerebral cortex and a significant increase in ChAT activity in the thalamus and hypothalamus. Meanwhile, the cerebral cortex, cerebellum, midbrain, thalamus and hypothalamus of the obese animals showed significantly higher AChE activity than their lean littermates. It was concluded from this study that obesity may be associated with changes in the enzymes of the brain cholinergic system.     

Involvement of D-amino acid oxidase in elimination of D-serine in mouse brain

The physiological role of D-amino acid oxidase (EC 1. 4. 3. 3) in mouse brain is described. The presence of D-enantiomers of neutral common amino acids was surveyed in the brain. D-serine was shown to be present at high concentration only in regions where the enzyme activity was low. In normal mice whose D-amino acid oxidase activity was much higher in the cerebellum than in the cerebrum, free D-serine content was apparently lower in the cerebellum than in the cerebrum. In mice of a mutant strain lacking D-amino acid-oxidase activity, the free D-serine level was remarkably high both in the cerebrum and cerebellum. The results suggest that the enzyme is involved in the elimination of free D-serine in the cerebellum.     

Involvement of D-amino acid oxidase in elimination of D-serine in mouse brain.

The physiological role of D-amino acid oxidase (EC 1. 4. 3. 3) in mouse brain is described. The presence of D-enantiomers of neutral common amino acids was surveyed in the brain. D-serine was shown to be present at high concentration only in regions where the enzyme activity was low. In normal mice whose D-amino acid oxidase activity was much higher in the cerebellum than in the cerebrum, free D-serine content was apparently lower in the cerebellum than in the cerebrum. In mice of a mutant strain lacking D-amino acid-oxidase activity, the free D-serine level was remarkably high both in the cerebrum and cerebellum. The results suggest that the enzyme is involved in the elimination of free D-serine in the cerebellum.     

Changes in the activities of protein kinase modulators in the cerebellum of mice due to ethanol, caffeine, or phenobarbital administration.

Decreased activities of both the inhibitory modulator of adenosine 3':5'-monophosphate (cAMP)-dependent protein kinase (A-PK) as well as the stimulatory modulator of guanosine 3':5'-monophosphate (cGMP)-dependent protein kinase (G-PK) from the mouse cerebellum were noted due to the administration of excessive doses of ethanol, caffeine, and phenobarbital for up to 28 days. The dose-dependent of the inhibition of A-PK or the stimulation of G-PK was observed as a function of the amount of protein kinase modulators in the cerebellum of mice receiving different doses of ethanol.     

The effects of acute and chronic morphine on regional distribution of cardiac output in brain

Both acute and chronic administration of morphine resulted in an increase in the percent cardiac output received by brain. However, various brain regions were affected differently by the drug treatments. The greatest increases in percent cardiac output received after chronic administration of morphine occurred in pons and cerebellum, while the greatest increases after acute administration occurred in cortex and midbrain. The changes found are in contrast with earlier studies which suggest that morphine has no effect on cerebral blood flow.     

Tele-encephalic versus cerebellar control upon ponto-geniculo-occipital waves during paradoxical sleep in the cat.

Studying the effects that removal of the cerebellum and the frontal lobes had upon the phasic activities (PGO waves) of paradoxical sleep in the cat, it is shown that in this phase of the sleep-wakefulness cycle the cerebellum exerts an inhibitory action upon the amplitude of the GPO, while the frontal lobes influences the pattern of their discharges.     

Effect of cortisone or triiodothyronine administration to pregnant rats on lysosomal hydrolases in fetal forebrain and cerebellum

Summary Triiodothyronine injected daily to pregnant rats for the last week of gestation (50 g/100 g b.wt) increased the specific activities of 5 acid glycosidases in the fetal forebrain and cerebellum. Cortisone (50 mg/100 g b.wt) administered in the same period had no effect on cerebellum acid hydrolases, but decreased their activity in the forebrain.Supported by grant No. HD 08536 from the National Institutes of Health, Bethesda, Maryland.     

The effects of acute and chronic morphine on regional distribution of cardiac output in brain

Summary Both acute and chronic administration of morphine resulted in an increase in the percent cardiac output received by brain. However, various brain regions were affected differently by the drug treatments. The greatest increases in percent cardiac output received after chronic administration of morphine occurred in pons and cerebellum, while the greatest increases after acute administration occurred in cortex and midbrain. The changes found are in contrast with earlier studies which suggest that morphine has no effect on cerebral blood flow.     

A sensitive and inexpensive high-performance liquid chromatographic assay for tyrosine hydroxylase

We describe a highly sensitive assay method for tyrosine hydroxylase (TH) using high-performance liquid chromatography with amperometric determination. This assay method could be applicable to any tissues with low enzyme activity, such as rat cerebellum. We also describe the kinetic properties of TH in rat cerebral cortex.     

Rhythmic cerabellar and cortical electric activity in tetanus intoxicated rabbits

Summary Intravenously injected tetanus toxin induced general tetanus within 12 to 37 h. The EEG of precentral, parietal, and occipital areas and of the cerebellum revealed a highly rhythmic activity. In local tetanus of the limbs or in brainstem tetanus this rhythm could not be registered.Parts of this paper were presented at the Spring Meeting of the German Pharmacological Society held in Mainz, March 1973.     

A sensitive and inexpensive high-performance liquid chromatographic assay for tyrosine hydroxylase

Summary We describe a highly sensitive assay method for tyrosine hydroxylase (TH) using high-performance liquid chromatography with amperometric determination. This assay method could be applicable to any tissues with low enzyme activity, such as rat cerebellum. We also describe the kinetic properties of TH in rat cerebral cortex.     

Neocortical transplants in the rat brain: an ultrastructural study

Electron microscopic analysis of neocortical transplants in the cerebellum of the host animals showed that the nerve cells, glial cells, and neuropil of the transplants were normal. These transplants showed anatomical integration with the host brain through various regions of interface. Neuropil interfaces were found to have a high density of synaptic profiles, and medullary interfaces had a very small number of synaptic profiles.     

Forskolin suppresses seizures induced by pentylenetetrazol in mice

Forskolin, an adenylate cyclase activator when injected s.c. (1 mg/kg) in mice, caused an elevation of cAMP in the forebrain and cerebellum of up to 170% and 130%, respectively. The treatment was found to prevent seizures induced by pentylenetetrazol. This suppression had subsided 30 min after the injection, when cAMP level was again normal in the cerebellum but still elevated in the forebrain.     

Thiamin turnover rate in some areas of rat brain and liver: a preliminary note.

Thiamin turnover rates in some nervous structures and liver of rats were evaluated in a steady state condition, using thiamin- 14C as a tracer. The radioactivity contents were analyzed by means of a mamillary type compartmental model. Excluding the liver, turnover rate values of the nervous structures were ordered in the following sequence: sciatic nerve (0.58 microgram/g . h) less than cerebellum less than hypothalamus less than midbrain less than corpus striatum less than cerebral cortex (0.16 microgram/g . h).