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E Ramon-Moliner

Publications and source records attributed to E Ramon-Moliner.

16 recordsLinked to original sources
PubMed1984

Subcortical projections of the pericruciate cortex of cat. An autoradiography study.

This communication deals with an autoratiographic analysis of two experiments in which multiple injections of 35S methionine were performed around the cruciate sulcus of cat. One case was studied in coronal sections and the other in sagittal sections. The thalamic projections include: (1) the anterior pole of nucleus reticularis; (2) the rostral pole of the ventral thalamus (VA and VL); (3) parts of the ventrobasal complex (VPLm and (VPM); (4) intralaminary centers, in particular CL; and (5) a region around the ventral end of the fasciculus retroflexus. Instead of a terminal projection, the latter appears to receive a system of collateral fibers which leave the cerebral peduncle at meso-diencephalic levels. An intricate pattern of negatively outlined centers was found. One of them ("nucleus Q") appears as a relatively large, non-labelled field within the ventrobasal thalamus, surrounded by a "halo" of labelled territories from which it is separated by a sharp outline. Other circumscribed negatively outlined fields appear as "islands" interposed between CL and VL. Surprisingly, hardly any target structures were seen beyond the mesencephalon, with the exception of the ipsilateral pontine nuclei and the so called lateral reticular nucleus of the medulla oblongata, contralaterally. The pyramidal tract was well labelled at all levels indicating a large projection to the spinal cord. The reason why no cortico-reticular projections were labelled is not clear.

Animals↗
PubMed1984

Diencephalic projections from rostral brain in cat. An autoradiographic study.

Following isotope injections in gyrus proreus (cases CT-600 and CT-601), the following nuclei were labelled: reticularis anterior, ventralis anterior, medialis dorsalis, ventralis medialis, medial portions of lateralis posterior, paratenialis and parafascicularis. Following an injection which included the medial precruciate and caudal genualis cortices (CT-625) the projection included: reticularis anterior, anterior medialis, ventralis anterior, ventralis anteromedialis, ventralis medialis, medialis dorsalis (pars paralamellaris), lateralis posterior, and parafascicularis. Thus, the medial precruciate cortex and the gyrus proreus share a number of projections. The most important differences are as follows: medialis dorsali principalis (both its medial magnocellular portion and its lateral parvicellular portion) receives afferents from gyrus proreus, whereas its paralamellar portion receives them from the medial precruciate and genualis cortices; the nucleus anterior medialis receives fibers from the medial precruciate cortex but not from gyrus proreus; a dorsolateral extension of VM, coined here as nucleus ventralis anteromedialis (VAM) receives fibers from medial precruciate but not from proreus cortex. No labelling was found in the hypothalamus, septum, and amygdala following injections in either proreus or medial precruciate cortices.

Animals↗
PubMed1982

A note on the corticocaudate connexions in cat.

Following injections of labelled amino acids around the pericruciate gyrus and the medial aspect of gyrus genualis-proreus in cat, two entirely different projection patterns are found in the head of the caudate nucleus. Massive and multiple pericruciate injections failed to label the most medial caudate nucleus which, by contrast, appears selectively labelled following genualis-proreus injections. The respective accepted connexions of pericruciate and genualis-proreus cortices with the thalamus and other subcortical structures are different. Therefore, it appears that the lateral and medial regions of the caudate nucleus must differ in their hodological and, possibly, in their functional characteristics.

Animals↗
PubMed1979

A retrothalamic system of collateral fibers from the cerebral peduncle.

Ramón y Cajal described a sizeable bundle of collateral fibers from the cerebral peduncle and called it 'faisceau de Forel'. This bundle has been consistently ignored by recent authors, possibly because of the difficulty to visualize it in transversal section. It is described here as the fasciculus prerubralis, or FPR. It originates at the level of the transition from the nucleus subthalamicus to the substantia nigra. In sagittal-stained sections of the mouse brain stained with the rapid Golgi method it can be seen following an ascending and nearly vertical course. It arches caudalwards, and appears to terminate in the rostral tegmentum. In the cat, Nauta-stained material proved that the corticofugal fibers which contribute to this system originate preponderantly, if not exclusively, in the pericruciate gyrus. Following lesions in this cortical area one could observe, in addition to the degenerating fibers of this bundle, another system of degenerating direct cortico-tegmental fibers which coursed toward the rostral tegmentum. It is not clear whether this second degenerating system resulted from the encroachment of passing fibers in the subjacent internal capsule. The tegmental prerubral collateral fibers from the cerebral peduncle were observed in mouse, rat and cat. Possibly, they could represent a general feature of the mammalian nervous system.

Afferent Pathways↗
PubMed1977

Non-synaptic chemical neurotransmission.

Images with apparently gemmulofugal polarity in the EPL of the olfactory bulb are the result of sectioning, along misleading planes, gemmulopetal synapses containing postsynaptic vesicles. Unless one accepts a bidirectional conduction for chemical synapses, the internal granule cells lack actual gemmulofugal synapses and the neurotransmitter contained on their vesicles must act at non-synaptic membranes.

Animals↗