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A Parent

Publications and source records attributed to A Parent.

At least 217 records · Page 12Linked to original sources
PubMed1981

Attempts to demonstrate peptide localization and secretion in primary cell cultures of fetal rat hypothalamus.

Primary cultures of dispersed hypothalamic cells were prepared from 18- to 19-day-old rat fetuses. Morphological studies revealed two types of cells having typical glial and neuronal appearances. Immunostaining of cells in culture was positive for neurophysin. The incubation medium contained radioimmunoassayable luteinizing hormone-releasing hormone, vasopressin, beta-endorphin and adrenocorticotropin hormone. The present data suggest that hypothalamic cells in primary culture secrete immunoreactive hormones or peptides; however, they do not seem to store significant amounts of these peptides.

Adrenocorticotropic Hormone↗
PubMed1981

Comparative anatomy of the serotoninergic systems.

A brief survey of our knowledge of the morphological organization of central 5-HT neuronal systems across phylogeny has revealed the following facts: 1. The 5-HT neurons seem to have occurred early in phylogeny. These neurons are already well-developed in the brain of cyclostomes (lampreys) and other primitive living vertebrates. 2. A similar pattern of topographical distribution of 5-HT cell bodies has been found in most vertebrates. These neurons are particularly abundant within the raphe region of the brain stem, whereas the catecholamine cells are more laterally located. In birds and mammals, where the 5-HT systems are strikingly well-developed, a certain degree of lateralization of the 5-HT systems has been noticed. This lead to a close intermingling of 5-HT and CA elements in these vertebrates. 3. The 5-HT neurons may act as an important informative link between the CSF and the neural tissue. In all nonmammalian vertebrates, a multitude of 5-HT cells was seen to be in direct contact with the CSF through short, club-like processes. The dense supraependymal plexus of 5-HT fibers disclosed in the rat brain could be the mammalian counterpart of these typical CSF-contacting cells. 4. The central 5-HT systems appear to be widespread and highly collateralized in all vertebrates. A single 5-HT raphe neuron may send divergent axon collaterals to various remote forebrain areas and, thus, could exert a rather diffuse influence over vast neuronal populations in all species. 5. The terminal arborizations of the 5-HT systems display patterns which are strikingly constant from one vertebrate class to another. Such a constancy in the structural organization of the 5-HT neurons strongly suggests that these neuronal systems are indeed phylogenetically ancient and subserve similar fundamental brain functions in all vertebrates.

Amphibians↗
PubMed1980

Acetylcholinesterase-containing neurons in cat neostriatum: a morphological and quantitative analysis.

When examined in brain sections prepared according to the Butcher's pharmaco-histochemical method, the large acetylcholinesterase (AChE)-containing cells in cat putamen appear morphologically different, more numerous per mm2, and significantly larger than those in caudate nucleus. Such a finding supports the view that the feline neostriatum is not a homogeneous structure. In addition, horseradish peroxidase (HRP) injected into the various target nuclei of neostriatum labels numerous medium-sized striatal cells and a few large-sized putaminal neurons. However, no HRP material could be detected in the large AChE cells themselves, suggesting that these cells are not output neurons.

Acetylcholinesterase↗
PubMed1979

Identification of the pallidal and peripallidal cells projecting to the habenula in monkey.

Injections of horseradish peroxidase (HRP) into the habenula of squirrel monkeys labeled a multitude of neurons in the lateal hypothalamus and a lesser number of neurons in the internal pallidum (GPi). The distribution of labeled cells is heterogeneous and many HRP-marked pallidal neurons are intermingled with acetylcholinesterase (AChE)-rich cells in the internal medullary lamina. However, these AChE neurons do not appear to contribute significantly to the innervation of the habenula. These findings suggest species differences between rodents and primates in regard to the organization of the pallidohabenular system.

Acetylcholinesterase↗
PubMed1979

Management of ventricular shunt infections.

The authors report the incidence (2.7%) of shunt infection in a series of 778 consecutive shunt procedures. The management of these infections and an additional group of infected patients operated elsewhere is discussed. A protocol is given for the treatment of external infections, gram-positive internal infections and gram-negative internal infections.

Anti-Bacterial Agents↗
PubMed1978

The organization of monoamine-containing neurons in the brain of the sunfish (Lepomis gibbosus) as revealed by fluorescence microscopy.

The morphological organization of the monoamine-containing neurons in the brain of the sunfish (Lepomis gibbosus) was studied by means of the Falck-Hillarp histofluorescence method. No attempt was made to distinguish between norepinephrine and dopamine, both primary catecholamines (CA) yielding a similar yellow-green fluorescence after paraformaldehyde treatment. In the brain stem of this teleost fish, three groups of CA-containing neuronal somata have been found. First, there is a small collection of CA perikarya located just caudal to the obex of the fourth ventricle. The neurons of this medullo-sinal group give rise to numerous CA fibers many of which ascend within the central portion of the medulla. Intermingled with these CA fibers are some CA cells that constitute the central medullary group. The CA perikarya of this group are scattered between the levels of cranial nerves X and VIII. The tegmentum of the isthmus also contains a small group of very closely packed CA neurons. The large-sized CA cells of the isthmal group are located dorsolateral to the medial longitudinal fasciculus, partly within the periventricular gray. High densities of CA varicosities were also disclosed in various brain stem structures such as the optic tectum, the torus semicircularis and the cerebeller valvula. In addition, numerous serotonin (5-HT)-type neuronal somata were found in the raphe region of the brain stem, particularly at caudal mesencephalic, isthmal and rostral medullary levels. A large number of CA cell bodies were visualized in the sunfish hypothalamus. Most of them form two populations of small, round cells that are located along and partly within the ependymal walls of the posterior and lateral recesses of the third ventricle. These bipolar cells possess one short club-like process protruding into the ventricle and their thin ependymofugal processes contribute to the CA innervation of numerous hypothalamic regions. Large CA neurons apparently without direct CSF contact also occur in the area of nucleus posterior tuberis, at the level of the mesodiencephalic junction. Although the hypothalamic inferior lobes are devoid of CA cell bodies they are heavily innervated by CA axons. The sunfish telencephalon also receives a strikingly massive and complex monoaminergic innervation. Numerous CA fibers which are first observed at the level of the preoptic area, ascend through the central zone of the telencephalon and arborize profusely particularly within the medial zone of area dorsalis telencephali. Other CA fibers, as well as abundant fine 5-HT varicosities were found in the lateral zone of area dorsalis. Although the exact origin of the telencephalic CA afferents in Lepomis is not known, part of it may arise from the isthmal CA cell group which appears similar to the locus coeruleus of reptiles, birds and mammals.

Animals↗
PubMed1978

Atlas of the distribution of monoamine-containing nerve cell bodies in the brain stem of the cat.

The distribution and morphological characteristics of monoamine (MA)-containing neuronal somata in the brain stem of kittens and of adult cats were studied by means of the Falck-Hillarp histofluorescence method. This investigation has shown, among other things, that in the midbrain of the cat the catecholamine (CA) perikarya are chiefly confined to the pars compacta of the substantia nigra, the ventromedial tegmental area, the nucleus linearis rostralis and the nucleus parabrachialis pigmentosus. Numerous CA neurons are also present in the dorsolateral part of the pontine tegmentum but also within the nucleus subcoeruleus, in nuclei lemnisci lateralis dorsalis and in nuclei parabrachialis lateralis and medialis. In the medulla, a few CA neuronal somata are lying near the hypoglossal nucleus whereas a larger number of CA cell bodies occur at the level of nucleus reticularis lateralis and in nucleus paragigantocellularis lateralis. On the other hand, most of the serotonin (5-HT) perikarya are confined to the raphe nuclei of the brain stem: nuclei raphe dorsalis, centralis superior, raphe pontis, raphe magnus, raphe pallidus and raphe obscurus. Some 5-HT neuronal somata are also found lateral to the pyramidal tract and to the inferior olivary complex. The various similarities and differences in respect to the pattern of the topographical distribution of MA neurons in the brain stem of the cat as compared to that of other mammals are discussed.

Animals↗
PubMed1978

[Comparative study of afferent connections in the habenula in rats and cats after injection of horseradish peroxidase].

The habenular complex of 11 cats and 13 rats was injected with horse Radish peroxydase (HRP) (30% solution, 0,05--0,4 microliter). Retrograde labelling of cells was visualized after a survival period of 24 to 48 hours by means of the method of Lavail et al. (1973). The resultats obtained with this method suggest significant species differences regarding the habenular afferents in cats and rats. One of the most striking differences is that the entopeduncular nucleus of the cat contains very few HRP labelled cells after lateral habenular nucleus injection in comparison to the entopeduncular nucleus of the rat which can be shown to be the major source of afferents to the lateral habenular nucleus by the same method.

Afferent Pathways↗
PubMed1977

Morphological characteristics of acetylcholinesterase-containing neurons in the CNS of DFP-treated monkeys. Part 2. Diencephalic and medial telencephalic structures.

The distribution and morphological characteristics of neurons containing acetylcholinesterase (AChE, EC 3.1.1.7.) in diencephalic and medial telencephalic structures of the rhesus monkey (Macaca mulatta) were studied by means of a pharmaco-histochemical method that involves staining for AChE (Karnovsky-Roots' procedure) at various times after the administration of di-isopropylfluorophosphate (DFP). At medial telencephalic levels, numerous, mostly multipolar, AChE-containing neurons of medium to large size are present in the bed nucleus of the anterior commissure, in the ascending division of the nucleus of the diagonal band of Broca, and in the so-called "substantia innominata". This last structure is composed of medial and lateral AChE cell groups that extend caudad, beneath the lenticular nucleus, for a considerable distance. The AChE neurons lying within the substantia innominata correspond, at least in part, to the basal nucleus of Meynert. Most neurons of the olfactory tubercle are devoid of AChE but lie within a lightly-stained AChE background. In addition, clusters of amorphous and highly reactive AChE material are found within the islands of Cajella and along the ventromedial edge of the olfactory tubercle. At the level of the thalamus, the strongest AChE staining is seen in the periokarya of the anterior dorsal nucleus and of most nuclei located within the fibrous or lamellar thalamic structures--i.e., the reticular nucleus, the intralaminar nuclei, and the midline nuclei except nuclei parataenialis and reuniens. In most of these nuclei the neuronal somata are of medium size and stain moderately for AChE. Their proximal processes are either lightly stained or devoid of AChE. At the level of the hypothalamus of the monkey, intense AChE staining can be seen within the neuronal somata of the supraoptic and paraventrivular nuclei. In the paraventricular necleus, the AChE-positive perikarya are of medium size and have numerous AChE-containing processes. Moderately reactive AChE neurons of smaller size with unstained processes are also present in the paraventricular nucleus. Most perikarya of the main rostral portion of the supraoptic nucleus are moderately stained for AChE, are closely packed, and their processes are difficult to discern. The main cellular aggregate of the supraoptic nucleus extends caudad and is composed of a large group of moderately to intensely stained neurons lying along the optic tract and which constitute the caudal, or infundibular, portion of the supraoptic nucleus. Other moderately to intensely stained AChE neurons were found in the lateral and perifornical areas and most particularly in the dorsal hypothalamic area. These neurons are of medium size and mostly multipolar. Moderately stained AChE neurons were also observed in the supramammillary nucleus, as well as those of the acruate nucleus, however, are only weakly reactive. The median eminence and most neurons of the ventromedial nucleus of the monkey hypothalamus are virtually devoid of AChE...

Acetylcholinesterase↗
PubMed1977

Morphological characteristics of the acetylcholinesterase-containing neurons in the CNS of DFP-treated monkeys.

The distribution of acetylcholinesterase (AChE, EC3.1.1.7) within extrapyramidal and related structures was studied in 4 monkeys following the i.m. administration of bis-(1-methylethyl) phosphorofluoridate (di-isopropylfluorophosphate: DFP). In 1 animal, sacrificed 4 hr after the injection of 0.43 mg/kg C, AChE is virtually absent in all structures. In the other 3 animals, which received 0.20 mg/kg DFP 10, 12 and 18 hr prior to sacrifice, AChE activity is greatly reduced in the neuropil of those structures which normally show intense AChE activity in pharmacologically unmanipulated monkeys. As a consequence of the lower background AChE activity in the latter 3 DFP-treated monkeys, the perikarya and processes of several groups of neurons can be readily identified. The perikarya and processes of two types of neurons of the neostriatum, representing a small percentage of all neurons in this structure, are intensely stained. They apparently correspond to the chromatic giant aspiny neurons and the achromatic medium-size "spidery aspiny" neurons. Most perikarya and processes of the neurons of the medial and lateral divisions of the pallidum, as well as the morphologically similar neurons of the pars reticulata of the substantia nigra, display light to moderate AChE activity. The pars compacta of the substantia nigra contains a small number of intensely stained elongated and triangular neurons and numerous moderately stained ovoid neurons whose processes are very lightly reactive. The cell bodies of the neurons of the subthalamic nucleus and associated groups of neurons (nucleus ansae peduncularis) are moderately stained whereas the perikarya and processes of the subnucleus compactus of the pedunculopontine tegmental nucleus are intensely and moderately stained, respectively. Numerous large and multipolar neurons associated with the lenticular nucleus (intralamellar groups) or the pallidum (peripallidal groups) including the nucleus ansae lenticularis have somata and processes which show an intense AChE activity. Certain of the latter groups of neurons, partially interspersed with the neurons of the substantia innominata, correspond in part to the nucleus basalis of Meynert. The present data are compatible with the idea that the large AChE neurons of the neostriatum may be the source of the acetylcholinesterasic striatopallidal and strionigral fibers. The similarity between the neurons of the pallidum and those of the pars reticulata of the substantia nigra suggests that the latter structure may represent a caudal extension of pallidal tissue. Therefore, the nigrothalamic projection, which has been claimed to originate in the pars reticulata of the substantia nigra, would correspond to pallidothalamic projections.

Acetylcholinesterase↗
PubMed1976

Organization and morphologies of acetylcholinesterase-containing neurons in the thalamus and hypothalamus of the rat.

The distribution and morphologies of neurons containing acetyl cholinesterase (AChE, EC 3.1.1.7) in the thalamus and hypothalamus of the rat were studied by means of a pharmaco-histochemical technique involving staining for AChE (Karnovsky-Roots' procedure) at various times after administration of bis-(u-methylethyl)phosphorofluoridate. This method enables visualization of individual AChE-containing neuronal somata and their processes to a degree not possible with other protocols for the enyzme. The strongest AChE activity occurring at the level of the thalamus is found within the small, round to oval, somata of nucleus anterior dorsalis. Most of the intralaminar nuclei, as well as nucleus reticularis, are composed of medium-sized multipolar neurons displaying moderate to strong AChE activity. Moderately stained AChE neurons are also found in pars ventralis of nucleus geniculatus lateralis and in pars lateralis of nucleus habenularis. Most of the neurons of the lateral and posterior thalamic territories, however, are nearly devoid of AChE. At the level of the hypothalamus, the neurons of nuclei supraoptics and paraventricularis show strong AChE activity. The AChE neurons of nucleus supraopticus are surrounded by numerous AChE-containing processes of some large lateral preoptic area neurons that stain intensely for the enzyme. Numerous intensely stained AChE perikarya occur in the lateral, dorsal, and supra-mammillary hypothalmic areas. These neurons often possess several AChE-containing processes. Nuclei arcuatus and ventomedialis consist mainly of neurons displaying a weak to moderate intensity of AChE staining. At the level of the mamillary bodies most neurons show moderate AChE activity except the neuronal somata of nucleus mammillaris lateralis which stain very strongly for the enzyme.

Acetylcholinesterase↗
PubMed1976

Striatal afferent connections in the turtle (Chrysemys picta) as revealed by retrograde axonal transport of horseradish peroxidase.

Horseradish peroxidase (HRP, 30% solution, 0.1-0.3 mul, 72 h) was injected unilaterally into the basal striatum (STR) and the dorsal ventricular ridge (DVR) of adult turtles (Chrysemys picta) in order to demonstrate the cells of origin of some afferents to these telencephalic structures. After selective STR injection, HRP-labeled cells were visualized in the dorsal thalamus and midbrain tegmentum, ipsilaterally. At thalamic level, HRP-positive neurons were located around nucleus rotundus, i.e., mainly within nuclei dorsomedialis anterior, dorsolateralis anterior and less abundantly in nuclei ventralis and reuniens. At midbrain level, a large population of labeled neurons was disclosed within the ventrolateral portion of rostral tegmentum. Other HRP-positive neuronal somata were found scattered throughout the lateral portion of the caudal midbrain tegmentum. In addition, labeled axons were visualized in both peduncles of the lateral forebrain bundle (LFB) after STR injection. The HRP-positive fibers of the dorsal peduncle of the LFB were followed up to the ipsilateral labeled thalamic cells where they appear to arise, whereas the HRP-containing axons of the ventral peduncle were traced down to the lateral midbrain tegmentum where they appear to arborize. Most of the HRP injections into the DVR were confined to the mediodorsal quadrant of the rostral half of the DVR. In such a case, a very large number of HRP-positive cells were disclosed within all thalamic nuclei surrounding nucleus rotundus, ipsilaterally. In addition, numerous labeled neurons were also found in nucleus rotundus itself and within nucleus reuniens. No HRP-positive cells were disclosed caudally to the meso-diencephalic junction after DVR injection.

Animals↗
PubMed1975

The monoaminergic innervation of the telencephalon of the frog, Rana pipiens.

A large number of serotonin (5-hydroxytryptamine, 5-HT)-type axon terminals has been visualized in the so-called 'striatum' (pars ventralis and dorsalis) of Rana pipiens by means of the Falck-Hillarp histochemical method. The frog striatum contains, however, a much smaller number of catecholamine (CA) type axon terminals and differs strikingly in that aspect from the neostriatum of 'higher' vertebrates which is known to receive a massive CA innervation. In the telencephalon of Rana pipiens the highest density of CA axon terminals occurs at the level of the medial wall, which appears highly hypertrophied in comparison to the thin lateral wall. The CA terminals are mainly concentrated within nucleus accumbens septi and in the ventrolateral portion of nucleus lateralis septi where they surround intimately the non-fluorescent neuronal somata of both septal nuclei. The three pallial fields (medial, dorsal and lateral) of Rana pipiens are nearly devoid of CA axon terminals. A moderate amount of 5-HT terminals is present, however, within the caudal half of both the medial and dorsal pallial fields. Finally, a few CA-type neuronal somata are found lying amongst the mitral cells of the olfactory bulb. As a whole, the telecenphalon of Rana pipiens appears more profusely innervated by axons of the 5-HT-type than by those of the CA-type. This finding has been related to the fact that in the frog brain stem the CA neuronal somata are scarce in comparison to the highly developed 5-HT neuronal systems.

Animals↗
PubMed1975

A fluorescence microscopic study of the distribution of monoamines in the hypothalamus of the cat.

Three distinct groups of monoamine (MA)-containing nerve cell bodies have been visualized in the hypothalamus and preoptic area of the cat by means of the Falck-Hillarp fluorescence histochemical technique. First, numerous small-sized catecholamine (CA) type neurons were disclosed within the ventral half of the periventricular area in the supraoptic and middle hypothalamic regions. The round to oval neurons of this medio-ventral group were more especially abundant around the base of the third ventricle, within the arcuate and supraopticus diffusus nuclei. Numerous medium-sized CA perikarya identified as the dorsal group, were also mapped out in the dorsal and posterior hypothalamic areas. Finally, a small population of both CA and serotonin (5-hydroxytryptamine, 5-HT)-containing neurons was disclosed within the lateral area of the middle and mammillary hypothalamic regions. These multipolar or elongated neurons which compose the lateral group were lying either along the ventrolateral surface of the hypothalamus or around the ventrolateral aspect of the fornix. In addition to these three MA cell groups, a few cells displaying a fluorescence of the CA type were also visualized in the so-called "dorsal chiasmatic nucleus" after alpha-methyl-dopa treatment. High density of CA axon terminals were found, on the other hand, in the extrenal layer of the median eminence, in the dorsomedial, paraventricular supraoptic and suprachiasmatic nuclei, and also within nucleus interstitialis of stria terminalis. In the present study, however, it was possible to identify with certainty any concentration of 5-HT axon terminals in the cat hypothalamus. Therefore, except for the lateral cell group which could be peculiar to the cat, the topographical distribution of MA nerve cell bodies and axon terminals in the hypothalamus of the cat appears similar to the morphological organization of the MA neuronal elements in the hypothalamus of the rat.

Animals↗