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A Fasolo

Publications and source records attributed to A Fasolo.

At least 109 records · Page 6Linked to original sources
PubMed1986

Habenular connections in the brain of the newt, Triturus cristatus carnifex Laurenti.

The connections of the habenular complex have been studied in the crested newt (Amphibia Urodela) by means of degeneration and HRP transport techniques. With the Fink-Heimer method, habenular efferents have been traced to the basal telencephalon, the pallium, the stria medullaris, the dorsal and ventral thalamus, the preoptic and anterior hypothalamus, the fasciculus retroflexus, the tegmentum and the interpeduncular neuropil. Anterograde transport of HRP by habenular neurons reveals fibers projections to the thalamus, the fasciculus retroflexus and the interpeduncular neuropil. After HRP injections in the habenulae, retrograde labelling of cells and fibres was observed, in the striatum, the posterior pole of the telencephalon, the thalamus, the preoptic area, the tegmentum and the raphe. The present results indicate that the habenular complex of the newt receives inputs of various sources (striatum, thalamus, hypothalamus, tegmentum) and is less directly involved in the olfactory functions.

Animals↗
PubMed1985

Active peptides from amphibian skin are also amphibian neuropeptides.

Immunohistochemical data on several newt brain areas showed a heterogeneous system of neuronal elements, immunopositive for antisera specifically directed to different antigenic determinants of tachykinin molecules. Acid extracts of newt brain areas were immunopositive for substance P with an antibody specific for the COOH-terminal (tachykinin determinant) and exhibits an elution profile by gel filtration characteristic to substance P. Bombesin-like immunoreactivity was demonstrable both by immunohistochemistry (fibers and cell bodies in forebrain and hypothalamic areas) and by radioimmunoassay, using an antiserum specific for the mid-region of the molecule. This immunoreactivity was separated into two peaks by gel filtration chromatography. Sauvagine-like material was detected by immunohistochemistry in newt hypothalamus as a loose preoptic cell system and as a thin fiber layer in the outer zone of the median eminence. Double staining procedures demonstrate that sauvagine and CRF are spatially closely related but separable in both the preoptic area and in the median eminence. This data on the presence of several amphibian skin peptides in the CNS of the newt suggests their possible role as neuropeptide.

Amphibian Proteins↗
PubMed1984

Immunohistochemical localization of corticotropin-releasing factor (CRF)-like immunoreactivity in the hypothalamus of the newt, Triturus cristatus.

The distribution of corticotropin-releasing factor (CRF) immunoreactivity was investigated in the hypothalamus and preoptic area of the newt by single and double immunocytochemical procedures. CRF immunopositive cell bodies were seen in the preoptic area (from the anterior wall of the preoptic recess to the dorsal parts of the preoptic nucleus) and in the tuberal portions of the posterior hypothalamus. Abundant nerve fibres are seen in the outer zone of the median eminence, while the pars nervosa lacks CRF-immunoreactivity. CRF immunoreactive material is seemingly separated from neurophysins- and somatostatin immunoreactive cell bodies and fibres.

Animals↗
PubMed1984

Immunohistochemical localization of substance P-like immunoreactivity in the hypothalamus of the lizard, Podarcis sicula, R.

The distribution of substance P (SP) immunoreactivity was investigated in the hypothalamus (preoptic area included) of the lizard by single and double immunocytochemical procedures, SP-immunopositive cell bodies were seen in the paraventricular nucleus and periventricular hypothalamic gray (including the paraventricular organ) together with some more lateral elements. Extensive nerve fibers were seen in the white matter and surrounding the paraventricular and supraoptic neurons, and more caudally reaching the hypothalamic periventricular gray, suggesting a massive involvement of SP-like substance in the control of hypothalamic neuroendocrine areas.

Animals↗
PubMed1983

The hypothalamus of Lacerta sicula R. II. A Golgi study of the preoptic area.

An analysis of the preoptic area of the lizard, Lacerta sicula R., with the use of the Golgi method revealed that: 1) in principle, the dendritic pattern of its neurons is relatively simple; 2) the supraoptic nucleus contains large- to medium-sized bipolar or multipolar neurons together with small, usually multipolar nerve cells; 3) the preoptic periventricular gray and the paraventricular nucleus exhibit a varied neuronal typology, including large multipolar or bipolar elements, abundant CSF-contacting neurons and some tufted elements; and 4) the lateral regions display some conspicuous multipolar neurons.

Animals↗
PubMed1982

The hypothalamus of Lacerta sicula R. I. A Golgi study on the caudal hypothalamus.

The posterior (caudal) hypothalamus of the lizard, Lacerta sicula R. was investigated by means of Golgi methods. The periventricular grey is formed mainly by isodendritic bipolar and multipolar neurons, while in the lateral hypothalamus a more stellate form of neuronal elements is encountered. CSF-contacting neurons are restricted to the tuberal area and to the paraventricular organ. In the latter area they are highly differentiated and endowed with laterally branched processes. The overall pattern of the lizard hypothalamus (organization of neuropil, lateral nuclei, appearance of cell clusters, morphology of the neuronal elements) represents an intermediate stage in the phylogenetic development of the hypothalamus, being more advanced than the amphibian stage.

Animals↗
PubMed1982

Ultrastructural analysis of the posterior hypothalamus of salamander.

The anatomical organization of the tuberal area of th posterior hypothalamus in Salamandra was investigated by the Golgi methods, SEM and TEM techniques. The ependymal cells of this area are poor in cilia and often show morphological features of actively secreting or absorbing elements. Intermingled with ependymal cells, two kinds of CSF-contacting processes are seen, arising from neurons of the periventricular grey. Their contents and morphological characteristics allow them to be divided into two groups, A and B. In the neuropil different synaptic contacts are seen. The observation of unconventional synaptic contacts possibly of axo-axonic type suggests the occurrence of local circuits on the final neurosecretory pathway.

Animals↗
PubMed1982

A Golgi study on neuronal morphology of the ventral lateral geniculate nucleus of the lizard.

The architecture and cellular morphology of the ventral geniculate nucleus (vLGN) of Lacerta sicula (Rafinesque) were investigated by means of classical neuroanatomical methods (Bodian, Klüver-Barrera, Cresyl-violet, and rapid Golgi impregnation). The vLGN of L. sicula is located in the laterodorsal portion of the diencephalon throughout the ventral thalamus. It appears sickle-shaped in cross section and contains a) a lateral neuropil, close to the marginal optic tract; b) a medial cell plate and c) an internal neuropil. Golgi preparations show a diffuse population of multipolar, "tufted" and bipolar neurons together with scattered glial cells in the lateral neuropil of vLGN. In the cell plate, two or three rows of cells of medium size, largely corresponding to the so called "cellule a doppio pennacchio" (Beccari, 1923) are found. These cells are endowed with two dendritic trunks, extending respectively into the internal neuropil and toward the optic tract. This latter process shows a quite complex arborization, closely intermingling with the retinal fibres arising from the marginal optic tract. The axons of these cells contribute to the fasciculus geniculatus descendens, the main efferent system of the vLGN.

Animals↗
PubMed1980

Substance P-related peptides in the hypothalamus of amphibia.

The occurrence of Substance P-(SP)-related peptides in the hypothalamus of three species of Amphibia (newt, clawed, toad, frog) was studied immunohistochemically employing the direct immunofluorescence method or a double-step technique (indirect immunofluorescence followed by the peroxidase-antiperoxidase complex method). SP-like immunopositive fibers are seen throughout the hypothalamus. They are especially abundant in the preoptic area and in the outer zone of the median eminence, suggesting a role of SP-related peptides in the hypothalamo-hypophysial regulation in these animals. Some SP-like neurons are seen in the posterior hypothalamus and in the preoptic area. In the newt, such SP-like immunopositive neurons occur frequently in the preoptic periventricular grey.

Animals↗
PubMed1978

A Golgi study of the hypothalamus of Actinopterygii. II. The posterior hypothalamus.

The posterior hypothalami of the polypteriform, Calamoichthys, and of the teleost, Anguilla, were studied by means of the Golgi technique. In Calamoichthys, the lateral lobes are not developed and the median lobe is simple. In Anguilla, the median (tuberal) lobe shows lophodendritic, CSF-contacting cells and horizontal cells in the periventricular grey and some reticular elements directed toward the cell-poor lateral areas. In the lateral lobes the periventricular grey is formed by multipolar neurons and a diffuse population of multipolar cells of uncertain identity. The nucleus diffusus lobi lateralis is formed by scarce multipolar neurons, often placed next to the external surface of the brain. The organization of the lateral lobes in Actinopterygii is reminiscent of highly developed integrative regions.

Anguilla↗
PubMed1978

A Golgi study of the hypothalamus of actinopterygii.

The preoptic area of a primitive actinopterygian, the polypteriform, Calamoichthys calabaricus Smithi, and of the teleost, Anguilla anguilla L., have been studied by Golgi and other neurohistological and histochemical methods. In the preoptic area two regions can be recognized: a cell rich median region and a lateral one, composed mostly of fiber systems. After Golgi staining a varied population of neurons is seen, including: (1) magnocellular neurons, endowed with a number of dendrites and an axon emerging from the main dendritic shaft; (2) lophodendritic tufted or pyriform neurons of variable morphology (often of the midget type); (3) cerebrospinal fluid contacting neurons; (4) bipolar and horizontal neurons. Of relevant interest is also the observation of commissural neurons, of a distinct precommissural necleus, and of bipolar neurons, the axons of which course toward the ventral hypopallium.

Anguilla↗
PubMed1977

The optic tectum of calamoichthys calabaricus Smithi. A Golgi study.

The optic tectum of Calamoichthys calabaricus (Polypteriformes) shows a relatively complex vertical stratification, with six main layers and a varied neuronal typology. In particular, pyriform neurons in the well developed stratum griseum periventriculare and some multipolar neurons in the stratum griseum profundum represent the efferent elements of the tectum, while the optic and lemniscal inputs to the tectum converge in the plexiform sublayers of the stratum fibrosum et griseum superficiale. In the circuitry of the tectum some modulation is achieved by some of the polymorphic cells of the stratum griseum internum and by the horizontal cells of the outer layers. Notwithstanding some differences with respect to the teleost optic lobe (i.e., the absence of a torus longitudinalis; the lack of a stratum fibrosum marginale; the modest size of the stratum fibrosum profundum; the paucity of neurons in the stratum fibrosum et griseum fibrosum profundum; the paucity of neurons in the stratum fibrosum et griseum superficiale; and the ill-defined separation of the layers of the afferent and efferent fibers), the optic tectum of Calamoichthys resembles the mesotectal type chracteristic of teleost, anurans and reptiles. It exhibits higher degree of organization than the optic tectum of the Chondrostei.

Animals↗
PubMed1977

A Golgi study on the hypothalamus of amphibia. The neuronal typology.

The neuronal typology in the hypothalamus of the frog and the crested newt was studied by the Golgi technique. In the newt, piriform, multipolar or cerebrospinal fluid (CSF)-contacting neurons of relatively primitive type, according to the classification of Ramón-Moliner, are encountered in the preoptic area. Moreover, magnocellular neurons are impregnated. In the frog the preoptic area shows a more varied typology. The posterior hypothalami of the frog and the newt exhibit mainly bipolar CSF-contacting and piriform neurons. These latter are generally "tufted", but some bipolar of multipolar cells are encountered, especially in the frog. The simple anatomical organization of the amphibian hypothalamus corresponds well with the pattern of "generalized" integrative area where multimodal sensory inputs converge--including visceral information from cerebrospinal fluid by means of hypothalamic CSF-contacting sensors--to regulate the neuroendocrine outflow.

Animals↗