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B Vigh

Publications and source records attributed to B Vigh.

At least 55 records · Page 3Linked to original sources
PubMed1982

Immunoreactive opsin in the pineal organ of reptiles and birds.

The presence of opsin was investigated with light microscopic immunocytochemistry in pinealocytes of reptiles and birds (Emys orbicularis, Pseudemys scripta elegans, Lacerta agilis et viridis, Gallus domesticus, Columba livia, Melopsittacus undulatus, Serinus canaria, Taeniopyga punctate). The outer segments of pinealocytes selectively bound antiopsin antibody as revealed by indirect immunocytochemical techniques, indicating the occurrence of a rhodopsin-like photopigment in these structures. The results were compared with those obtained in retinal photoreceptors of the same species as well as in the pineal organ of fishes and amphibians (Cyprinus carpio, Carassius auratus, Rana esculenta). Corresponding to immunoreactive structures seen in the light microscope, we found typical outer segments on a large number of pinealocytes in most of the reptiles and birds studied. The presence of opsin in the numerous well developed pineal outer segments of these reptilian and avian species contradicts the earlier hypothesis on the gradual regression of pineal sensitive structures in the avian line of evolution.

Animals↗
PubMed1981

Light- and electron-microscopic demonstration of immunoreactive opsin in the pinealocytes of various vertebrates.

An antibody to opsin isolated from rod outer segments of the frog retina was applied in light- and electron-microscopic immunocytochemical studies to the pineal organ of various vertebrates (Cyprinus carpio, Carassius auratus, Rana esculenta, Emys orbicularis, Pseudemys scripta elegans, Lacerta agilis and viridis. Gallus domesticus, Columba livia, Melopsittacus undulatus, Serinus canaria, Taeniopyga punctata, Didelphis virginiana, Erinaceus roumanicus, Myotis myotis, rabbit, rat, cat).

Animals↗
PubMed1980

Immunohistochemical localization of substance P and ACTH-like activity in the central nervous system of the earthworm Lumbricus terrestris L.

The peroxidase-antiperoxidase (PAP) method was used for the immunohistological demonstration of substances P and ACTH in the cerebral and subesophageal ganglia of the earthworm, Lumbricus terrestris L. With rabbit antibody to substance P a positive immunoreaction was found in nerve cells smaller than the type A neurons of the cerebral ganglion. Their perikarya and nerve processes as well as their terminal enlargements in the synaptic zone were immunoreactive. ACTH-like activity was visible in a larger perikaryon type of the A neurons. Their nerve processes did not show any reaction. However, a part of the nerve terminals of the synaptic zone and a few neurons of type B of the cerebral ganglion, further some cells of the subesophageal ganglion reacted positively.

Adrenocorticotropic Hormone↗
PubMed1980

Immunocytochemical studies on the central nervous system of the earthworm, Lumbricus terrestris.

There are numerous aldehyde fuchsin (AF)-positive, neurosecretory cells of medium size (A cells) and a small number of large, AF-negative neurons (B cells) in the cortical layer of the cerebral ganglion. In the subesophageal ganglion, symmetrical groups of AF-positive cells lie ventrally. The peroxidase--antiperoxidase (PAP) method was used for the immunocytochemical study of substance P and ACTH in these ganglia. In addition, the presence of L-enkephalin and alpha endorphin could be confirmed. Using rabbit antibodies to substance P we found small immunoreactive neurons among negative A and B cells in the cerebral ganglion. The processes of these immunoreactive cells could be traced to the subcortical synaptic neuropil. With antibodies to ACTH, activity was visible in perikarya similar in size to A neurons. A part of the nerve terminals of the synaptic zone, some of the B neurons and further several nerve cells of the subesophageal ganglion reacted positively. Successive demonstration of substance P and ACTH on the same section showed that the two materials occurred in different cell types. Using antiopsin antibody in an indirect immunocytochemical test we observed strong reaction in numerous medium-sized perikarya and in nerve fibres of the synaptic zone of the cerebral ganglion, further in some neurons of the subesophageal and abdominal ganglia. In contrast to this result, the photoreceptor cells of the prostomium and cerebral ganglion were negative. Presumably, substance P is present in a perikaryon type hitherto unrecognized while ACTH and antiopsin reactions seem to be located first of all in A cells.

Adrenocorticotropic Hormone↗
PubMed1980

Ciliated perikarya, "peptidergic" synapses and supraependymal structures in the guinea pig hypothalamus.

There are numerous nerve cells giving rise to solitary cilia of type 9 x 2 + 0, in the hypothalamic areas studied (medial preoptic nucleus, supraoptic and paraventricular nuclei, anterior periventricular nucleus, wavy paraventricular ependyma, and infundibular wall), further in the precentral gyrus and cerebellar flocculus. In the hypothalamic nuclei, the perikarya contained granular vesicles of varying sizes (800 A to 1800 A in diameter). In the supraoptic nucleus, a second neuron type was described among the lateral optic fibres. These nerve cells differ from the main neurosecretory ones by the size of their granular vesicles and their high number of large axo-somatic synapses formed by myelinated axons. In the paraventricular nucleus, axons may terminate on the basal lamina of vessels. A subependymal neuron group was described near the wavy paraventricular ependyma. The subependymal hypothalamic neuropil is characterized by various kinds of synapses including apparent "peptidergic" ones, and by axo-glial synaptic connections. The latter are also present on the apica surface of the ependyma in various regions of the 3rd ventricle. In addition, intraventricular structures (dendrites, axons, neuronal and non-neuronal perikarya, synapses) were studied by scanning (SEM) and transmission electron microscopy (TEM).

Animals↗
PubMed1980

Comparison of the pineal complex, retina and cerebrospinal fluid contacting neurons by immunocytochemical antirhodopsin reaction.

The presence of rhodopsin was investigated by an indirect immunocytochemical method in the pineal complex of various vertebrates (Carassius auratus, Cyprinus carpio, Hypophthalamichthys molitrix, Lucioperca lucioperca, Triturus vulgaris, Bombina bombina, Rana esculenta, Pseudemys scripta elegans, Lacerta agilis et viridis, white leghorn chickens, rat), in the retina of Lebistes reticulatus, Lucioperca lucioperca, Rana esculenta, Lacerta agilis, Pseudemys scripta elegans, the chicken and the rat, and the cerebrospinal (CSF) contacting neurons of Triturus vulgaris. The outer segments of the photoreceptor terminals of the pineal organ, frontal organ, parapineal organ of lower vertebrates and of the retina of the species investigated, were intensely stained with the antirhodopsin reaction. There was no significant positivity in the pineal organ of the reptiles, the chicken and the rat, and the parietal eye of the lizards. We failed to demonstrate any immunoreactive staining in the CSF contacting neurons of various hypothalamic areas and of the spinal cord. The light microscopic immunocytochemical results seem to contradict a photoreceptive role of the CSF contacting neurons and strengthen the view that the receptory cells of the pineal complex of lower vertebrates are involved in light perception by means of the visual pigment rhodopsin.

Amphibians↗
PubMed1979

A comparison of epithalamic, hypothalamic and spinal neurosecretory terminals.

Nerve endings of epithalamic, hypothalamic and spinal neurosecretory areas were studied by light and electron microscopy in various vertebrates (from fishes up to mammals) including the lancelet. Areas investigated were the pineal organ, the pulvinar corporis pinealis, the neurohypophysis, the median eminence, the urophysis, the terminal filum and the medullo-spinal neurosecretory zones. We found that in all these areas the neurosecretory endings have common structures, which we call synaptic hemidesmosomes or neurohormonal terminals. These are characterized by accumulation of vesicles, and dense projections in a terminal on the basal lamina of the surface of the nervous tissue. A critical review of the literature suggests that a considerble neuroendocrine activity is associated with synaptic hemidesmosomes as special neurohormonal effector structures of the nerve cells. The cell-to-cell synapses formed by neurosecretory cells are discussed in connection with the dual capacity of these cells to function as both endocrine and "ordinary# neuronal elements. The importance of the external cerebrospinal fluid (CSF) space for the transport of materials released in the so-called neurohemal areas, is stressed.

Amphibians↗
PubMed1979

Scanning and transmission electron microscopy of intraventricular dendrite terminals of hypothalamic cerebrospinal fluid contacting neurons in Triturus vulgaris.

A scanning (SEM) and transmission electron microscopic (TEM) study of the ventricular wall of the hypothalamus of Triturus vulgaris was performed with special regard to the intraventricular dendrite terminals of the cerebrospinal fluid (CSF) contacting neurons of the preoptic area (magnocellular and parvocellular preoptic nuclei), the infundibular lobe (anterior periventricular nucleus, infundibular nucleus), and the paraventricular organ. In the preoptic area and infundibular lobe, the terminals were knob-like or club-shaped, of various sizes (diameter about 0,5 to 3,0 micrometer) and located immediately above the ependyma. Ultrastructurally, they may contain dense-core vesicles of varying sizes. The CSF contacting dendrite endings of the paraventricular organ built up a supraependymal labyrinthic layer which could be divided into a rostral crest-like part and a caudal flat and broad division. In both parts, three main types of terminals of various size and shape could be distinguished: a) ramifying, b) elongated, and c) bulb-like dendrite endings which also differed by their TEM structure. The bulk-like terminals, first of all the small ones, originated from the distal part of the nucleus of the organ (nucleus organi paraventricularis) while the other two types took their origin from its intra- and subependymal part. In all areas investigated, each intraventricular dendrite ending gave rise to a solitary cilium (type 9 X 2 + 0). It differed from the ependymal kinocilia by both SEM and TEM characteristics. In the paraventricular organ, the neuronal cilia were hidden inside, or below the supraependymal layer of terminals. There were intraventricular axons which formed synapses on CSF contacting dendrite endings of both parts of the paraventricular organ. Free intraventricular neurons, further ependymal areas heavily or scarcely ciliated, were described. The CSF contacting dendrite terminals were predominantly present near ventricular recesses and in regions where the ependyma was scarcely ciliated.

Animals↗
PubMed1978

Scanning electron microscopy of the prostomium and anterior segments of the earthworm (Lumbricus terrestris L., Eisenia foetida Sav.).

A scanning electron microscopic study of the epithelium of the prostomium, anterior segments, mouth and pharynx was performed in Lumbricus terrestris L. and Eisenia foetida Sav. Numerous ciliated areas (number of cilia up to 800) identified as receptor organs, were found scattered on the prostomium and 1st segment. From the 2nd segment on, the number of organs decreased and they were arranged in several rows. Receptor organs small in size and number, were also found in the buccal and pharyngeal epithelium. The cilia of the sensory organs stuck out of holes of different sizes of the epithelial cuticle thickened by a supracuticular matrix. In addition, there were groups of about 5 cilia scattered below the epithelial cuticle. Each cilium lay in a narrow groove of the subcuticular surface of the epithelium characterized by an abundance of short thick microvilli protruding into evenly sized holes of the cuticle. The cilia appeared to be identical with those of solitary sensory cells.

Animals↗
PubMed1977

Special dendritic and axonal endings formed by the cerebrospinal fluid contacting neurons of the spinal cord.

The cerebrospinal fluid (CSF) contacting neurons have a dendritic process which protrudes into the central canal, and is provided with one long kinocilium and many shorter stereocilia (about 80 in the turtle) as revealed by scanning electron mecroscopy. The shape, number and arrangement of the cilia are similar to those of known receptor endings. The silver impregnated axons of these cells converge to a paired centrosuperficial tract forming terminal enlargements at the ventrolateral surface of the spinal cord. Lying among glial endfeet these terminals are ultrastructurally similar to those present in known neurosecretory areas. The nerve endings are attached to the basal lamina, and they comprise many synaptic vesicles (200 to 400 A in diameter), as well as granular vesicles of different sizes (diameter 600 to 1800 A). The axons may lie within finger-like protrusions on the surface of the spinal cord, or they may terminate around vesseles. Morphological evidence suggests that these nerve terminals and the corresponding CSF contacting perikarya represent a spinal neurosecretory system possibly influenced by information taken up by its special dendrites protruding into the inner CSF space.

Amphibians↗
PubMed1977

Intra- and extraganglionic nerve endings formed by neurosecretory cells of the cerebral ganglion of the earthworm (Lumbricus terrestris L.).

In the cerebral ( = supraesophageal, suprapharyngeal) ganglion of the earthworm, a number of neurosecretory Gomori-positive perikarya are bipolar; others are unipolar, or multipolar. Some of the neurosecretory cell processes project centrally into a fibrous zone; peripheral processes enter small nerves which leave the dorsocaudal aspect of the ganglion. In the central fibrous zone, the neurosecretory fibers form varicose Gomoripositive terminals. Here, also zinc-iodine-osmium (ZIO)-positive fibers and monoamine fluorescent fibers are found. With the electron microscope, nerve terminals containing synaptic vesicles and either large neurosecretory "peptidergic" granular vesicles (diameter more than 1500 A), or smaller granular vesicles (diameter about 1300 A, or 900 A) are observed. These axon endings mainly form axo-dendritic synapses. "Peptidergic" profiles are both pre- and postsynaptic. Some of the extraganglionic "peptideric" fibers appear to terminate around vessels, but most of them form terminals on the visceral muscle cells which surround the ganglion. We think that the central neurosecretory processes communicate with the fibers of the synaptic zone of the ganglion. The peripheral neurosecretory "peptidergic" fibers are supposed to form a primitive neurohemal area and/or to function as vasomotor nerves. The fibers innervating the visceral muscle cells may represent vegetative nerves.

Animals↗
PubMed1976

Ciliated neurons and different types of synapses in anterior hypothalamic nuclei of reptiles.

The magnocellular paraventricular and supraoptic nuclei and the parvocellular preoptic and periventricular nuclei have been studied by light and electron microscopy in Emys orbicularis, Lacerta agilis and Elaphe longissima. The ultrastructure of cerebrospinal fluid (CSF)-contacting neurons was described in the preoptic and periventricular nuclei of Emys and Lacerta species. Single 9 X 2 + 0 cilia similar to those of the CSF-contacting dendritic terminals were found on perikarya of non CSF-contacting nerve cells, in all four investigated nuclei. The cilia project from funnel-like invaginations of the perikarya into the intercellular space. In the neurons of the nuclei studied, granular vesicles were found, their size being mainly 1,600 A in the paraventricular nucleus, about 1,800 A in the supraoptic nucleus, 1,100 A in the periventricular nucleus and 800 A, or up to 1,250 A in the preoptic nucleus. In general, the neurons possess synapses of the axo-somatic, axo-somatic spine, axo-dendritic and axo-dendritic spine types. In the supraoptic nucleus, multiple interdigitated synapses were observed. Presynaptically, eif different sizes (600 to 800 A, about 1,100 A, 1250 A, and up to 2,000 A) were found. It is discussed whether the above described 9 X 2 + 0 cilia may represent some kind of hypothalamic sensory structure that earlier physiological studies postulated to exist. The ciliated hypothalamic perikarya are considered by the authors to be a more differentiated form of the CSF-contacting neurons. The different types of synapses indicate multilateral connections of the nerve cells of the nuclei studied.

Animals↗
PubMed1976

Cerebrospinal fluid-contacting neurons, ciliated perikarya and "peptidergic" synapses in the magnocellular preoptic nucleus of teleostean fishes.

The magnocellular preoptic nucleus of fishes (Anguilla anguilla, Amiurus nebulosus, Cyprinus carpio, Carassius auratus, Ctenopharyngodon idella, Cichlasoma nigrofasciatum) has been studied by light and electron microscopy. Two kinds of neurons Were found: a) large, electron-dense, Gomori-positive cells with moderate acetylcholinesterase (AChE) positivity which contain granulated vesicles of 1400 to 2200 A (in average 1600 to 1800 A), adn b) small, strongly AChE-positive, electron-lucent neurons containing granulated vesicles of 900 to 1200 A. The nerve cells are supplied with axo-somatic and axo-dendritic synapses. These are formed by axon terminals containing either 1. synaptic vesicles of 500 A, or 2. synaptic vesicles of 500 A and dense-core vesicles of 600 to 800 A, or 3. synaptic vesicles of 600 A and granulated vesicles of up to 1100 A, or 4. synaptic vesicles of about 400 A and granulated vesicles of up to 1800 A. The presence of "peptidergic" and numerous other synapses shows the complexity of the organization and afferentation of the magnocellular preoptic nucleus. In the eel, both types of nerve cells form dendritic terminals within the cerebrospinal fluid (CSF). These CSF contacting dendrites are supplied with 9 x 2 + 0 cilia. In the other species investigated, only some large neurons build up intraventricular endings. The ependymofugal process of the CSF contacting neurons enters the preoptic-neurohypophysial tract. Perikarya of both the large and the small cells may give rise to single, paired or multiple 9 x 2 + 0 cilia extending into the intercellular space. The number of CSF contacting neurons is reciprocal to the number of perikarya with intercellular cilium. These latter cells may represent modified, more differentiated forms of the CSF contacting neurons. We think that atypical cilia protruding into the intercellular space may have the same significance for the intercellular fluid as the cilia of the intraventricular dendrites of the CSF contacting neurons for the CSF.

Acetylcholinesterase↗
PubMed1975

Comparative ultrastructure of cerebrospinal fluid-contacting neurons and pinealocytes.

The pinealocytes of fishes, amphibians, reptiles, birds and mammals have been compared with cerebrospinal fluid (CSF) contacting neurons. We found that the intraventricular dendrite terminal of the latter resembles the pinealocytic inner segment and that the atypical cilium (9x2+0 tubules) of the CSF contacting neurons is analogous with the outer segment of the pinealocytes, even though the outer segment bears photoreceptor lamellae in lower vertebrates. Regular, but small-sized photoreceptor outer segments were also found on pinealocytes of the chicken. In mammals, too, primitive outer segments are present in the form of 9x2 to cilia similar to those of CSF contacting dendritic terminals. In the Golgi areas of the perikarya of both cell types there are granulated vesicles which may contain transmitter substances and/or neurohormones. The synaptic junctions of the pinealocytes differ from those in the CSF contacting neurons. Many synapses occur on the latter, but they appear only rarely on pinealocytes. The axons of the CSF contacting neurons form synaptic connections with other cells, or terminate as neurohormonal synaptic hemidesmosomes on the basal lamina of the brain surface. The pinealocyte axons give rise to terminals containing synaptic ribbons. Such ribbons do not occur in CSF contacting neurons. In Lacertilians, we found pinealocytic terminals without ribbons on dendrite-like profiles. On the basis of the ultrastructural comparisons, we consider the CSF contacting neurons and pinealocytes to be very similar, but not to represent precisely the same cell type.

Animals↗