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J Storm-Mathisen

Publications and source records attributed to J Storm-Mathisen.

At least 127 records · Page 7Linked to original sources
PubMed1981

K+-evoked Caa+-dependent release of D-[3H]aspartate from terminals of the cortico-pontine pathway.

Pontine nuclei dissected from rat brain slices released previously accumulated D-[3H]aspartate (D-Asp) and [14C]gamma-aminobutyrate (GABA) Ca-dependently when exposed to 50 mM K. These efflux rates were substantially increased by including 0.5 mg/ml bovine serum albumin in the superfusion fluid. Degeneration of the cortico-pontine fibres 5 days after cutting the crus cerebri caused an 80% reduction in the fractional rate of Ca-dependent D-Asp release and a 60% reduction in uptake. The fractional rate of GABA efflux was significantly less reduced than that of D-Asp efflux, and GABA uptake was nearly unchanged.

Animals↗
PubMed1981

Glutamate in hippocampal pathways.

The three consecutive main excitatory neurone projections in the hippocampal formation (the perforant path, the mossy fibres and the pyramidal cell axons) all show acidic amino acid uptake in their terminals. This is in accordance with other data pointing to the transmitter function of glutamate and/or aspartate in the perforant path and pyramidal cell axons. In the mossy fibres the role of these amino acids has so far not been determined. The localization of glutamate and aspartate uptake in the excitatory axon systems contrasts with the localization of GABA uptake in the axons of the inhibitory basket cells and other short axon neurones.

Animals↗
PubMed1979

Tentative localization of glutamergic and aspartergic nerve endings in brain.

1. The locations of the high affinity uptakes of glutamate, aspartate and GABA were studied autoradiographically and microchemically in slices of hippocampus and septum in vitro. 2. In hippocampus the distributions of the uptake sites for glutamate and aspartate were very similar, with much higher uptake in zones containing pyramidal cell terminals than in other zones. A reciprocal distribution was found for GABA uptake, which was in agreement with that of GAD. 3. Cutting pyramidal cell axons to CAl reduced the uptake of aspartate and glutamate in the target area in CAl by 80%. 4. Autoradiographically the uptake of aspartate was very high in the dorsal part of the lateral septum, moderately high in nucleus accumbens septi and neostriatum, and very low in the medial septum. GABA uptake was lower in the medial than in the lateral septum, but very high in a narrow transitional zone and in the insula Cajella magna. 5. Transecting the axons from hippocampus and subiculum to septum, gave a 70% reduction in the uptakes of aspartate and glutamate in the lateral septum, but no reduction in the medial septum. 6. Literature data on uptake, content and release of glutamate and aspartate in nerve endings in brain are briefly reviewed.

Animals↗
PubMed1977

Localization of tissue thromboplastin in the human brain.

Monospecific antisera against the purified protein component of tissue thromboplastin (apoprotein-III) from human brain have been raised in goats and rabbits. The antisera neutralized tissue thromboplastin prepared from brain, thyroid gland and pulmonary tissue, indicating that apoproteins in the various preparations cross-reacted immunologically and therefore were similar or identical. Comparison of the activities of tissue thromboplastin preparations from 34 different areas of the brain demonstrated a characteristic distribution pattern and a wide range of activities. White and grey matter from the same areas had similar activities. Bulbus and tractus olfactorius, medulla oblongata, corpus pineale, hippocampus and hypothalamus contained 160-270% of the average activity, whereas cerebellum globus pallidus, nucleus ruber and substantia nigra contained 30-60%. The distinct distribution pattern was unrelated to tissue vascularization, and may suggest that apoprotein-III could serve other functions, apart from the coagulation of blood. The predominance in phylogenetically older brain regions would suggest that it represents a primitive or fundamental feature.

Animals↗
PubMed1977

Localization of putative transmitters in the hippocampal formation: with a note on the connections to septum and hypothalamus.

Biochemical assays on microdissected samples, denervation studies, subcellular fractionation, and light and electron microscopic autoradiography of high affinity uptake have been performed to study the cellular localization of transmitter candidates in the rat hippocampal formation. High affinity uptake of glutamate and aspartate is localized in the terminals of several excitatory systems, such as the entorhino-dentate fibres (perforant path), mossy fibres (from granular cells) and pyramidal cell axons. Thus, in stratum radiatum and oriens of CA1, 85% of glutamate and asparate uptake and 40% of glutamate and aspartate content are lost after lesions of ipsilateral plus commissural fibres from CA3/CA4. Hippocampal efferents also take up aspartate and glutamate, since these activities are heavily reduced in the lateral septum and mamillary bodies after transection of fimbria and the dorsal fornix. The synthesis (by glutamic acid decarboxylase), content and high affinity uptake of gamma-aminobutyrate (GABA) are not reduced after lesions of these or other projection fibre systems. A localization in intrinsic neurons is confirmed by a selective loss of glutamic acid decarboxylase after local injections of kainic acid. Peak concentrations of the enzyme occur near the pyramidal and granular cell bodies, corresponding to the site of the inhibitory basket cell terminals, and in the outer parts of the molecular layers. Some 85% of glutamic acid decarboxylase is situated in 'nerve ending particles'. Acetylcholine synthesis (by choline acetyltransferase) disappears after lesions of septo-hippocampal fibres. Since 80% of the hippocampal choline acetyltransferase is in 'nerve ending particles', the characteristic topographical distribution of this enzyme should reflect the distribution of cholinergic septo-hippocampal afferents. Serotonin, noradrenaline, dopamine and histamine are located/synthesized in afferent fibre systems. Some monoamine-containing afferents to the hippocampal formation pass via the septal area, others via the amygdala. The hippocampal formation also contains nerve elements reacting with antibodies against neuroactive peptides, such as enkephalin, substance P, somatostatin and gastrin/cholecystokinin.

Acetylcholine↗
PubMed1975

High affinity uptake of GABA in presumed GABA-ERGIC nerve endings in rat brain.

After interuption of the striato-nigral pathway uptake of gamma-aminobutyric acid (GABA) in the substatia nigra decresaed with 7 days to a constant level 30-40% of the normal. Concomitantly glutamate decarbosylase (GAD) was reduced to 10%. Hence about two-thirds of the GABA uptake activity in substantia nigra are localised, to the alleged GABA-ergic nerve elements originating from corpus striatum. The lesion resistant part of the uptake is probably not localised in cell bodies or large processes, since it was the same in tissuse prisms as in whole homogenates and crude nerve ending fractions. It was also not influenced by aminoozyacetic acid, which would argue against a localisation in glia. Whereas GAD was recovered mainly in a "heavy" nerve ending fraction, a large proportion of the GABA uptake was situated in a "light" fraction. After hemisections, GABA uptake was reduced to a similar extent in both fractions. It is suggested that whereas GAD is concentrated in nerve terminals, a significant proportion of the GABA uptake may be localised in preterminal axon branches in the substantia nigra. GABA uptake in the dorsal part of the lateral vestibular nucleus was not reduced by interruption of the Purkinje axons from the cerebellar vermis whereas GAD was reduced 50%. This indicates that the reuptake mechanism is not concentrated in the Prukinje axon terminals. In the hippocampus neither GABA nor GAD were reduced by lesions of afferent nerve pathoways, in accordance with previous results showing that in this region GABA producing neurones are intrinsic. The order of ratiols of GABA uptake to particulate GAD activity in different regions was: hippocampus greater than cerebellar cortex greater than substantia nigra greater than dorsal part of lateral vestibular necleus approximately equal to nucleus interpositus. The ratio may relfect the degree of specific localisation of the GABA uptake mechanism to the GABA-ergic structures.

Aminobutyrates↗