The fine structure of cloned cells from normal adult rat brain

Summary A cell clone was isolated from a normal adult rat brain culture and maintained in vitro for many passages. It possessed glial characteristics; in particular ultrastructural examination revealed astrocytic features including the presence of filaments 9–11 nm in diameter.Acknowledgments. The work was partly supported by a grant from the Cancer Research Campaign to JPR. The secretarial help of Miss Hilary A. Waddington is gratefully acknowledged.     

The influence of antistine on glycogenolytic effect of some biogenic amines in rat brain slices

Résumé On a démontré que l'antistine empêche in vitro l'effet glycogénolytique de l'histamine, bien qu'elle n'ait pas d'influence sur les actions glycogénolytiques de la noradrénaline, de la dopamine, de la sérotonine, du 3, 5-AMP cyclique et de son dérivé dibutirique. Ces résultats suggèrent l'existence de récepteurs particuliers pour les amines biogénique dans le tissue du cortex, du nucleus caudatus et du thalamus. De ces résultats on a conclu que, dans le cerveau du rat, l'adénocyclase pourrait être le récepteur histaminique.     

The influence of propranolol and dibenzyline on glycogenolytic effects of some biogenic amines in rat brain slices

Résumé On montre que le propranolol empêche les effets glycogénolytiques de la noradrénaline et de la dopamine, bien qu'il n'ait pas d'effet sur les actions glycogénolytiques de l'histamine, de la sérotonine, du 3,5-AMP cyclique et de son dérivé dibutyrique. On en conclu qu'au niveau du cervau des rats l'effet glycogénolytique des catécholamines résulte de l'excitation des récepteurs adrénergiques et que les autres unités régulatrices les adénylcyclases sont responsables des effets de l'histamine et de la sérotonine.     

Changes of X-prolyl dipeptidyl-aminopeptidase activity in developing rat brain

Summary We found X-prolyl dipeptidyl-aminopeptidase activity in rat brain and examined the developmental changes at various ages. The total enzyme activity per brain increased until 4 weeks of age, and then decreased during maturation. Specific activity in young rat brain was higher than that in adult rat brain. The properties of the brain enzyme were different from those of pituitary and other tissues.     

Uptake of some amino acids by rat brain slices: Effect of various substrates

Résumé En milieu de Krebs-Ringer oxygéné et glucosé, les coupes de cortex cérébral de Rat accumulent les acides aminés contre un gradient de concentration. L'anoxie, l'exclusion du substrat, et les inhibiteurs métaboliques inhibent cette accumulation. Parmi les substrats de la chaîne glycolytique et du cycle de Krebs étudiés, le succinate et le fumarate donnent les niveaux d'accumulation les plus réduits. On observe très généralement une corrélation entre la teneur des composés phosphorylés riches en énergie, et l'accumulation active des acides aminés.     

Changes of X-prolyl dipeptidyl-aminopeptidase activity in developing rat brain.

We found X-prolyl dipeptidyl-aminopeptidase activity in rat brain and examined the developmental changes at various ages. The total enzyme activity per brain increased until 4 weeks of age, and then decreased during maturation. Specific activity in young rat brain was higher than that in adult rat brain. The properties of the brain enzyme were different from those of pituitary and other tissues.     

Parathion metabolism in rat liver and kidney slices

Zusammenfassung Es werden quantitative Angaben über die Bildung von Paraoxon aus Parathion und seine weitere Aufspaltung durch Inkubation mit Leber- und Nierenschnitten und Rattendarm gemacht. Unter der Voraussetzung, dass die Inkubation der Gewebeschnitte im wesentlichen den Verhältnissen im Organismus entsprechen, würde das die Umwandlung bewirkende Enzymsystem im Verlaufe von 24 h etwa 75% des anwesenden Parathions zu Paraoxon überführen.     

Organophosphate-mediated inhibition of choline acetyltransferase activity in rat brain tissue

Administration of the organophosphate compound soman in rats resulted in an inhibition of choline acetyltransferase activity in almost all brain regions examined. Enzyme activity was inhibited by 20-50% in various brain regions 30 min after soman injection (94-120 micrograms/kg). Enzyme activity in two regions decreased with time to a near zero level by 3 h after injection.     

Organophosphate-mediated inhibition of choline acetyltransferase activity in rat brain tissue

Summary Administration of the organophosphate compound soman in rats resulted in an inhibition of choline acetyltransferase activity in almost all brain regions examined. Enzyme activity was inhibited by 20–50% in various brain regions 30 min after soman injection (94–120 g/kg). Enzyme activity in two regions decreased with time to a near zero level by 3 h after injection.Research sponsored by the Air Force Office of Scientific Research/AFSC, United States Air Force, under Contract F49620-82-C-0035. This work was also supported by PHS MBRS Grant No. RR08037. The cooperation of Dr G. Goddard of the School of Aerospace Medicine, Brooks AFB, is gratefully acknowledged.     

An assessment of the effect of hormone and neurotransmitters on adenine and gluanine derivatives simultaneously in rat brain cortical slices

Summary A 2-dimensional thin-layer method has been developed for the separation on cellulose of adenine and guanine derivatives. Using incubated rat cerebral cortex slices it was shown that noradrenaline and acetylcholine stirnulated cAMP and cGMP production respectively but glutamate and -aminobutyric acid stimulated production of both cyclic nucleotides.     

Contribution of diffusive pathway in intestinal absorption of glucose in rat under normal feeding condition

Summary Luminal concentration of glucose determined by a specific enzymatic method was about 50 mM after meal in rat jejunum. The diffusive pathway was suggested to have an important role in intestinal absorption of glucose.     

The effect of 5-hydroxytryptophan on the efflux of noradrenaline from brain slices

Zusammenfassung 5-Hydroxytryptophan erniedrigt die Konzentration von Noradrenalin in Hirnschnitten, sofern diese das Amin zuvor aus zugesetzteml-DOPA selber synthetisierten. Dieser Effekt beruht vermutlich darauf, dass 5-Hydroxytryptophan die Decaroxylierung desl-DOPA, das im Hirngewebe gespeichert wird, kompetitiv hemmt. Die Relation der Noradrenalin- und Serotoninkonzentration im Hirngewebe kann somit auch durch ein verändertes Angebot an Aminosäuren gestört werden.     

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.     

Altered brain cholinergic enzymes activity in the genetically obese rat

Summary 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 and 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.This work was supported by a grant from the National Aeronautics and Space Administration (NAG 2-411), a grant from the National Institutes of Health (NIH RR 0811), and a grant from the Division of Research Resources, National Institutes of Health (NIH Grant RR 03020).