Immunohistological investigations of N-Acetylserotonin in the rat cerebellum after parachlorophenylalanine treatment

Summary The amount of N-acetylserotonin (NAS) in the granule layer of the rat cerebellum was investigated using immunohistologic double antibody technique. After 5 days of treatment with parachlorophenylalanine (PCPA) an increase of NAS was observed. The possibility of a differential effect of PCPA on serotonin synthesis in the neurons and the nerve terminals is discussed.     

Immunohistological localization of melatonin in the rat digestive system

Summary The highest amount of melatonin (M), localized immunohistologically, was found in rectum, decreasing in the order: colon, duodenum, caecum, esophagus, stomach, ileum and jejunum. No M was found in the liver, spleen or pancreas. The distribution of M corresponds with the localization of serotonin-producing argentaffin cells.     

Cilia in stellate neurons of the rat cerebellum

Summary Cilia in stellate neurons of the normal rat cerebellum are described. 8 cilia were observed in a total of 60 cells studied. An 8+1 pattern was found throughout their length. Furthermore, no arms, spokes or other accessory structures necessary for ciliary motion were seen. These findings make it possible to suggest that these cilia are probably without function and are related to the epithelial origin of these cells.This work was granted by INIC: Centro de Morfologia Experimental (MbP₁).Acknowledgments. The authors thank M.A. Rodrigues, M. M. Pacheco, M. C.Pinho and L. B. Nunes for technical assistance.     

Monolayer cultures of perikarya isolated from postnatal rat cerebellum.

Viable cerebellar perikarya of mixed cell type obtained from 7--9-day-old rats were maintained in monolayer cutlure for up to 12 days. During this time extensive neurite formation and outgrowth occurred. The large majority of the cells developing in culture were tentatively identified as granule neurons. This identification was based on the large number isolated from the starting tissue, and the cells' general morphological features in culture such as perikaryal and nuclear size, the bipolar nature of neurite extension, and their migratory behaviour.     

Neuritic plaque-like structures in the rat cerebellum following prolonged alcohol consumption

Primitive neuritic plaques were observed in the inner third of the molecular layer of the cerebellar cortex of rats following chronic alcohol consumption. Neurites were identified as dystrophic parallel fiber boutons. Amyloid material dispersed among neurites was not clearly recognized, dystrophic some fibrils were frequently seen among them. Astrocytic processes were noted in the periphery of the plaque. Microglial reaction, however, was non-existent. The rarity of these lesions in the rat cerebellum and their probable relation to long periods of alcohol consumption is discussed.     

Neuritic plaque-like structures in the rat cerebellum following prolonged alcohol consumpotion

Summary Primitive neuritic plaques were observed in the inner third of the molecular layer of the cerebellar cortex of rats following chronic alcohol consumption. Neurites were indentified as dystrophic parallel fiber bouton. Amyloid material dispersed among neurites was not clearly recognized, dystrophic some fibrils were frequently seen among them. Astrocytic processes were noted in the periphery of the plaque. Microglial reaction, however, was non-existent. The rarity of these lesions in the rat cerebellum and their probable relation to long periods of alcohol consumption is discussed.This work was granted by I.N.I.C., project MbPl, and Stiftung Volkswagenwerk, project I/37424.     

Estimation of the methylating capacity in the pineal gland of the rat with special reference to the methylation of N-acetylserotonin and 5-hydroxytryptophol separately

Summary In the present paper, an extension is presented of an earlier described method, by which the methylating capacity of the pineal gland can be determined. Supplementary to the earlier method, the synthesis of melatonin and 5-methoxytryptophol can now be qualified and quantified separately.The authors wish to express their gratitude to Prof. Dr J.C. van de Kamer and Dr F.C.G. van de Veerdonk for their stimulating interest in these studies.     

Monolayer cultures of perikarya isolated from postnatal rat cerebellum

Summary Viable cerebellar perikarya of mixed cell type obtained from 7–9-day-old rats were maintained in monolayer culture for up to 12 days. During this time extensive neurite formation and outgrowth occurred. The large majority of the cells developing in culture were tentatively identified as granule neurons. This identification was based on the large number isolated from the starting tissue, and the cells general morphological features in culture such as perikaryal and nuclear size, the bipolar nature of neurite extension, and their migratory behaviour.D.N. Currie was supported by a grant from Hoechst Pharmaceuticals, Ld, U.K.J.C. was supported by an S.R.C. Grant to S.P.R. RoseThe authors would like to thank Kathleen Tear for excellent technical assistance and members of the Brain Research Group for helpful discussions.     

Effects of chronic lesions of the peduncles on cerebellum cholinesterase activity,in the albino rat

Riassunto Lesioni unilaterali nell'ambito dei peduncoli cerebellari sono seguite, nel ratto, da una caduta dell'attività colinesterasica vera del cervelletto, che raggiunge i valori massimi del 60% nella metà ipsilaterale e del 40% in quella controlaterale nel caso di sezione totale dei tre peduncoli. In nessun caso l'attività della pseudo-colinesterasi è risultata significativamente modificata.     

Depletion and repletion of noradrenaline in adrenergic nerves of the rat after decaborane treatment

Zusammenfassung Mit Hilfe der Fluoreszenz-Technik werden die Veränderungen in sympathischen Fasern der Ratteniris nach Noradrenalin-Depletion durch Boron-Hydrid Decarboran (Dopa-Dekarboxylase-Hemmer) analysiert.

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This work has been supported by grants from the Swedish Medical Research Council under project No. B70-14x-97-06B, B70-14x-711-05B and Knut and Alice Wallenberg Foundation.     

The effect of unilateral cerebellar pedunculotomy on the vascular development of the neonatal rat cerebellum

After cerebellar pedunculotomy the density of the blood vessel network in the cerebellar cortex was not different from that in the control animals. But the pattern of the blood vessels was different, being less organized in the operated animals.     

On the norepinephrine replacement by α-methyl-norepinephrine in the rat heart after treatment with α-methyl-DOPA

Résumé Des rats ont été traités une fois par jour pendant 11 jours avec de l'-méthyl-DOPA ou de l'-méthylnoradrénaline. Le 12^e jour, le taux de la noradrénaline cardiaque était de 15% par rapport aux contrôles. Les curs avaient en outre fixé une quantité d'-méthyl-noradrénaline nettement supérieure au déficit en noradrénaline. Après arrêt du traitement, la remontée du taux de la noradrénaline s'est accompagnée d'une perte correspondante d'-méthyl-noradrénaline. Après normalisation complète du taux de la noradrénaline, l'-méthyl-noradrénaline était encore présente dans le cur en quantité à peu près égale à celle de la noradrénaline, et fixée apparemment dans un dépôt relativement inerte.