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R Elde

Publications and source records attributed to R Elde.

At least 91 records · Page 5Linked to original sources
PubMed1988

Corticotropin-releasing factor in cerebellar afferent systems: a combined immunohistochemistry and retrograde transport study.

The flocculus and paraflocculus of cat and sheep cerebellum were studied with immunohistochemical methods, using antisera to corticotropin-releasing factor (CRF). CRF immunoreactivity was present within 3 populations of varicose nerve fibers. One population of CRF-immunoreactive (CRF-IR) fibers appeared to appose Purkinje cell somata and to follow their dendrites into the molecular layer. This arrangement suggested they were climbing fibers. A second group of CRF-IR profiles reminiscent of mossy fibers was widely distributed throughout the granule cell layer. A third population of CRF-IR fibers was present as a beaded plexus lying parallel to the pial surface, above and subadjacent to the Purkinje cell layer. The fibers of this plexus extended into the Purkinje cell layer and surrounded these somata. The source of some of the CRF-IR fibers within the flocculus and paraflocculus was determined by a retrograde axonal transport study utilizing the fluorescent tracer Fast blue (FB) in combination with the immunohistochemical localization of CRF. It was determined that CRF-IR perikarya within the inferior olivary nucleus gave rise to a population of climbing fibers within those lobules. Furthermore, all divisions of the inferior olive were found to contain CRF-IR somata. This latter finding suggests the potential for CRF-IR climbing fiber projections from the inferior olive to other regions of the cerebellar cortex. The existence of CRF-IR mossy fibers and fibers within the ganglionic plexus suggests the possibility of CRF-IR afferent projections from other regions of the brain stem to the flocculus and paraflocculus.

Afferent Pathways↗
PubMed1987

Simultaneous observation of fluorescent retrogradely labeled neurons and the immunofluorescently labeled fibers apposing them using Fluoro-Gold and antisera labeled with the blue fluorochrome 7-amino-4-methylcoumarin-3-acetic acid (AMCA).

In this paper we describe a method allowing the simultaneous observation of fluorescent retrogradely labeled neurons and the immunofluorescently labeled fibers which appose them. This technique employs the fluorescent dye Fluoro-Gold to label neurons retrogradely, and 7-amino-4-methylcoumarin-3-acetic-acid (AMCA) conjugated to a secondary antiserum as a label for fluorescence immunohistochemistry. Both Fluoro-Gold and AMCA are excited by near-ultraviolet (UV) light, but under UV excitation Fluoro-Gold appears yellow and AMCA appears blue. Thus the two fluorochromes are both visible under a single condition of illumination and can be readily distinguished by color. This allows quick and accurate determination of whether or not immunofluorescent fibers appose retrogradely labeled neurons.

Animals↗
PubMed1987

Distribution of cholecystokinin-immunoreactive cell bodies in the male and female rat: I. Hypothalamus.

The hypothalamic distribution of cholecystokinin-immunoreactive (CCKI) cell bodies in colchicine-treated male and female rats was studied. Immunoreactive neurons were visualized along the anterior two-thirds of the third ventricle but were especially numerous in the preoptic periventricular nucleus. Dense aggregations of CCKI cells were found in the anterior magnocellular, posterior magnocellular, medial parvicellular, and posterior parvicellular divisions of the paraventricular nucleus. Both the supraoptic nucleus and the central, cell-dense part of the dorsomedial nucleus contained large numbers of CCKI cells. CCKI cells in the preoptic periventricular nucleus were more numerous in the female, as was a population of labeled cells in the dorsal medial preoptic area. However, CCKI cell bodies in this part of the medial preoptic area were larger in males than in females. Males had more CCKI cells in the central part of the medial preoptic nucleus and in the posterior magnocellular subdivision of the paraventricular nucleus. Both males and females had similar numbers of immunoreactive cells in the anterior magnocellular and the parvicellular divisions of the paraventricular nucleus as well as in the anterior hypothalamus, dorsal areas, dorsomedial nucleus, and supramammillary region. These data provide morphological evidence for a sexually differentiated hypothalamic CCKI system.

Animals↗
PubMed1987

Glutamic acid decarboxylase- and peptide-immunoreactive neurons in cortex cerebri following development in isolation: evidence of homotypic and disturbed patterns in intraocular grafts.

Fetal parietal cerebral cortex was transplanted to the anterior eye chamber of adult Sprague-Dawley rats. After two to three months the grafts, with or without colchicine treatment, were subjected to immunohistochemical analysis using antibodies against cholecystokinin (CCK), somatostatin (SOM), neuropeptide tyrosine (NPY), vasoactive intestinal polypeptide (VIP), peptide histidine isoleucine (PHI) and the GABA-synthesizing enzyme glutamic acid decarboxylase (GAD). Cerebral cortex in situ of untreated and colchicine-treated rats was always analyzed in parallel. A dense plexus of CCK-immunoreactive fibers was distributed in all parts of the transplants, and after colchicine treatment a large number of CCK-positive cells was observed. These cells were markedly increased in number as compared to normal cortical tissue in colchicine-pretreated rats. The amount of NPY-immunoreactive cells was also markedly increased, whereas somatostatin-positive cells were found in numbers similar to those seen in cortex in situ. In the grafts only a few VIP- and PHI-positive fibers were seen with a few VIP-positive cell bodies, but no clearly discernible PHI-positive cells. A very dense plexus of GAD-positive fibers with an even distribution throughout the grafts was observed. Cortex in situ exhibited a lower density of GAD-immunoreactive fibers. Even after colchicine treatment the number of GAD-positive cells in the grafts was low. Using double-staining techniques, it was found that most of the few GAD-positive cells in the grafts were also NPY-positive, SOM-positive or, to a minor extent, CCK-positive. The present results demonstrate that several peptides and transmitter markers are expressed in cortical grafts in oculo, but marked differences in their expression can be observed in cortical tissue that has developed in isolation. Thus, the intraocular cortex graft, alone and in combination with other brain areas, should provide a useful model in which to study factors that regulate brain development.

Animals↗
PubMed1987

The coexistence of serotonin- and substance P-like immunoreactivity in the spinal cord of the rat as shown by immunofluorescent double labeling.

This study surveyed the coexistence of serotonin-like immunoreactivity (5-HT-IR) with substance P-like immunoreactivity (SP-IR) in fibers and terminals within various portions of the spinal cord of the rat. A previously characterized technique of immunofluorescent double labeling was used to stain 5-HT-IR red and SP-IR green, and a search was then made for single fibers that fluoresced both colors. These were found to be most common in the ventral horn, wherein 99% of 5-HT-IR fibers were also immunoreactive for SP. Coexistence of these substances was very rare in the superficial dorsal horn: fewer than 3% of 5-HT-IR fibers were immunoreactive for SP. In the region surrounding the central canal and in the intermediolateral cell column (IML), over half of all 5-HT-IR fibers and terminals were doubly labeled. In the white matter, doubly labeled fibers were most common in the ventral funiculus and somewhat less common in the lateral funiculus. They were rare in the dorsal columns. It is concluded that the coexistence of 5-HT and SP in nerve fibers and terminals is associated with somatic and sympathetic autonomic motoneurons. The role of the coexistence of 5-HT and SP in somatosensation, including pain, is unclear.

Animals↗
PubMed1986

Immunohistochemical localization of urotensin I/corticotropin-releasing factor, urotensin II, and serotonin immunoreactivities in the caudal spinal cord of nonteleost fishes.

Neurosecretory cells in the caudal spinal cord of fishes were first discovered in elasmobranches. However, most of the subsequent work on the caudal neurosecretory system has emphasized its morphology and function in teleosts. Two major peptides, urotensins I and II (UI and UII), have been isolated from this system in teleosts and their amino acid sequences have been determined. We have used immunohistochemical techniques to confirm and expand previous morphological and pharmacological findings regarding the phylogenetic occurrence and the anatomical organization of the caudal neurosecretory system and to localize putative neurohormonal products within its structural elements. UII-immunoreactive neuronal structures were found in the holocephalan, Hydrolagus collei; the elasmobranches, Squalus acanthias, Dasyatis sabina, and Raja binoculata; the dipnoan, Protopterus annectens; the brachiopterygian, Erpetoichthys calabaricus; the chondrostean, Polyodon spathula; and the holosteans Lepisosteus platyrhinchus and Amia calva. UI/corticotropin-releasing-factor immunoreactive elements were detected in the caudal spinal cords of Petromyzon marinus, Raja binoculata, Polydon spathula, Lepisosteus platyrhinchus, L. osseus, L. platostomus, and Amia calva. In addition, in several of these species, immunohistochemical techniques have provided evidence for serotoninergic input to the caudal neurosecretory system.

Animals↗
PubMed1986

Coexistence of urotensin I/corticotropin-releasing factor and urotensin II immunoreactivities in cells of the caudal neurosecretory system of a teleost and an elasmobranch fish.

By use of the indirect immunofluorescence method in conjunction with an elution-restaining technique, cells in the caudal neurosecretory system of the big skate (Raja binoculata) and the plainfin midshipman (Porichthys notatus) were shown to contain both urotensin I (UI)/corticotropin-releasing factor (CRF) and urotensin II (UII) immunoreactivities. In the skate coexistence was complete, while in the midshipman some cells demonstrated immunoreactivity for only one or the other neuropeptide. The present results do not support previous suggestions that, like vasopressin and oxytocin in the hypothalamic magnocellular system, UI and UII exist in separate cellular populations in the caudal neurosecretory system. Results of these and other experiments indicate that there exists a wide range of species variation in the degree of coexistence of UI/CRF and UII immunoreactivities within caudal neurosecretory cells.

Animals↗
PubMed1986

Topography of NPY-, somatostatin-, and VIP-immunoreactive, neuronal subpopulations in the guinea pig celiac-superior mesenteric ganglion and their projection to the pylorus.

The topography of the peptidergic neuronal subpopulations in the guinea pig celiac-superior mesenteric ganglion was studied analyzing the distribution of immunoreactivity to neuropeptide Y (NPY), somatostatin (SOM), and vasoactive intestinal polypeptide (VIP)/polypeptide HI (PHI). For comparison, the ganglion was also studied using antisera against the 2 catecholamine-synthesizing enzymes tyrosine hydroxylase (TH) and dopamine beta-hydroxylase (DBH). Approximately 65% of the neuronal cell bodies contained NPY-like immunoreactivity (NPY-LI), whereas 25% of the principal ganglion cells contained SOM-like immunoreactivity (SOM-LI). Though occasional cells were found to contain both NPY-LI and SOM-LI, these peptides had a complementary distribution in the ganglion, with NPY cells in the celiac poles and SOM cells in the superior mesenteric pole. The vast majority of both the NPY- and SOM-positive cells also contained TH-like immunoreactivity (TH-LI), confirming their catecholaminergic, presumably noradrenergic, nature. Some noradrenergic neurons seemed to lack NPY- and SOM-LI. Small numbers of VIP/PHI-containing cell bodies were found in areas where the NPY-immunoreactive neurons predominated. Many of the VIP/PHI-positive cells contained NPY-LI and occasionally also TH-LI. The immunohistochemical markers were also observed in fibers. Thus, a comparatively weak NPY-LI was seen in smooth fibers, probably representing axons and axon bundles. SOM-LI was seen in a similar type of fiber but also in more strongly fluorescent fibers with a varicose appearance. The latter fibers were observed only in the SOM-dominated part of the ganglion, often surrounding the ganglion cells. Varicose fibers with a similar distribution containing DBH-like immunoreactivity (DBH-LI) were also seen. In addition, DBH- and TH-LI were seen in smooth axonlike processes. VIP-positive fibers exhibited a very dense fiber network, almost exclusively related to the SOM cell-dominated part of the ganglion. The projection of the postganglionic sympathetic neurons was studied with special reference to the pylorus using a combination of retrograde axonal tracing and indirect immunofluorescence techniques. Seventy-two hours after injection of the fluorescent tracer Fast Blue into the pyloric sphincter, labeled neurons were found in the ganglion. By comparing the Fast Blue-labeled cells with the immunoreactive cell bodies, neurons containing both dye and NPY- or SOM-LI were observed. In elution-restaining experiments, it was established that the majority of these cells were also immunoreactive to TH, indicating that they produce noradrenaline.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1985

Immunocytochemical studies of somatostatin neurons in brain.

Immunohistochemical studies with antisera to somatostatin have, in many instances, led the way to our present understanding of the peptidergic nervous system. Somatostatin was among the first of the hypophysiotropic hormones shown to be contained in diverse neuronal circuits outside of the hypothalamus. For example, somatostatin is found within neurons ranging in location from the cerebral cortex to primary sensory neurons to enteric neurons within the gut wall. Somatostatin was also the first neuropeptide demonstrated to coexist within vertebrate neurons that also produce a classical neurotransmitter. Since this initial demonstration in sympathetic ganglionic neurons, somatostatin and numerous other neuropeptides have been demonstrated to coexist with a variety of classical neurotransmitters. The "rules" for coexistence are not clear, since somatostatin coexist in some instances with norepinephrine, in other cases with GABA, and probably with other classical transmitters as well. In some neurons, somatostatin also coexists with certain other neuropeptides. Finally, the specificity of immunohistochemical localizations of somatostatin has now been confirmed by virtue of the co-staining of somatostatin neurons with antisera to other portions of the biosynthetic precursor to somatostatin.

Animals↗
PubMed1984

Peripheral projections and neuropeptide coexistence in a subpopulation of fluoride-resistant acid phosphatase reactive spinal primary sensory neurons.

Combined retrograde axonal tracing with the fluorescent dye Fast Blue and fluoride-resistant acid phosphatase (FRAP) histochemistry revealed that the FRAP-containing sensory neurons project to both somatic and autonomic peripheral nerves. Furthermore, the combination of indirect immunohistochemistry after colchicine treatment and FRAP histochemistry showed that a population of FRAP-containing sensory neurons are also substance P, cholecystokinin or somatostatin positive.

Acid Phosphatase↗
PubMed1984

Effects of cysteamine on pain behaviour and on somatostatin- and substance P-like immunoreactivity in the substantia gelatinosa of the rat.

Immunohistochemical studies on rats showed cysteamine to deplete immunoreactive somatostatin, but not substance P, in the substantia gelatinosa of the spinal trigeminal nucleus and spinal cord. The effect of cysteamine treatment on chemical pain was investigated using capsaicin as the pain-producing stimulus. Thermal pain was assessed with a hot plate test after cysteamine treatment. It was found that cysteamine did not alter the hind paw lick latency in the hot plate test or the number of forepaw wipes after application of a drop of capsaicin into the cornea, compared to normal animals. In capsaicin-treated animals a significantly lower number of forepaw wipes were seen after corneal capsaicin application. However, in cysteamine-treated animals slower wiping was observed compared to untreated and capsaicin-treated animals. This suggests that somatostatin may be of importance for the modulation of nociceptive information, although it is not a major pain transmitter.

Animals↗
PubMed1984

Peptidergic regulation in neuroendocrine and autonomic systems.

Neuropeptides are found in dense networks of neuronal perikarya, fibers and terminals within numerous brain regions. Among the more striking of these collections are sites within the central nervous system that are presumed to regulate either endocrine or autonomic function. A recent example of a neuropeptide which is likely to play a significant role in endocrine regulation is cortocotropin releasing factor (CRF). Immunohistochemical studies revealed that CRF immunoreactivity was found in many brain regions, including the paraventriculo-infundibular pathway. CRF released from nerve terminals belonging to this pathway presumably regulates ACTH release. Treatment of rats with reserpine depletes CRF as well as vasopressin from the external layer of the median eminence, suggesting tonic, monoaminergic inhibition of CRF and vasopressin containing neurons. CRF antisera were found which stain urotensin I immunoreactivity within the caudal neurosecretory system of fish. Numerous putative neurotransmitters impinge upon preganglionic sympathetic neurons within the intermediolateral cell column of the spinal cord. Preganglionic sympathetic neurons which innervate the adrenal medulla appear to have a specific input from somatostatin immunoreactive fibers. In addition, binding sites for serotonin and alpha-2 adrenergic ligands are more highly concentrated over sympathoadrenal neurons. Finally, the pancreatic islet contains peptide producing endocrine cells which possess several neuron-like properties. Some of these properties are reviewed, especially the finding that the insulin producing cells contain glutamate decarboxylase immunoreactivity, the biosynthetic enzyme for GABA. Further studies revealed that GABA agonists inhibit somatostatin release from islet cells.

Adrenal Medulla↗
PubMed1984

Immunohistochemical localization of urotensin I/corticotropin-releasing factor immunoreactivity in neurosecretory neurons in the caudal spinal cord of fish.

Urotensin I (UI), one of the biologically active peptides isolated from the caudal spinal cord and urophysis of fish, exhibits a strong sequence homology with mammalian corticotropin-releasing factor (CRF). We have applied an antiserum to ovine CRF that cross-reacts completely with UI to sections taken from the caudal spinal cord and urophysis of the channel catfish (Ictalurus punctatus). Using the indirect immunofluorescence technique, the presence of striking UI-like immunoreactivity was observed within discrete neuronal structures. UI immunoreactivity was found within large-diameter neuronal perikarya in spinal cord segments immediately rostral to the urophysis, in fascicles of nerve fibers as the urophysis emerges, and in a dense plexus of nerve fibers and terminals which abut capillary loops within the urophysis. The localization of UI immunoreactivity within discrete neurosecretory neurons of this system will make it possible to more fully determine the nature of the regulatory mechanisms controlling its secretion.

Animals↗
PubMed1984

Selective localization of the parathyroid secretory protein-I/adrenal medulla chromogranin A protein family in a wide variety of endocrine cells of the rat.

Secretory protein-I (SP-I) of parathyroid glands and chromogranin A ( CGA ) of adrenal medullary chromaffin cells are chemically similar if not identical proteins. Both proteins are contained within secretory granules and appear to be cosecreted with granule contents, for example, in the parathyroid with PTH and in the adrenal with epinephrine and dopamine beta-hydroxylase. Antisera to bovine SP-I and porcine CGA , together with antisera to a variety of peptide hormones, were used in an immunofluorescence study of rat tissues in order to determine the probable distribution and cellular localization of these proteins. In addition to their previously demonstrated presence in parathyroid and adrenal cells, the SP-I/ CGA protein family was detected in cells of the thyroid that contained calcitonin and often SRIF but not thyroglobulin; in cells of the anterior pituitary staining for the alpha-subunit of TSH/FSH/LH but not in cells staining for GH, PRL, ACTH, or beta-endorphin; in pancreatic islet cells staining for SRIF and pancreatic polypeptide-related peptides, but not for insulin or glucagon; in the celiac and mesenteric ganglia in cells some of which contained SRIF; and in the gastric antrum in cells containing SRIF, but not gastrin. SP-I/ CGA was not detected in cells of the liver, kidney, parotid gland, or acinar pancreas or in the intermediate or posterior lobes of the pituitary. These results suggest that this protein family enjoys a widespread but highly restricted distribution in many different endocrine-peptide cells of the rat, many that are believed to be of the APUD cell series. The possibility is raised that SP-I/ CGA plays some physiological role in the secretory process or exerts an effect of its own in the periphery after secretion.

Adrenal Medulla↗
PubMed1983

The nucleus tractus solitarii of the cat: a comparison of Golgi impregnated neurons with methionine-enkephalin- and substance P-immunoreactive neurons.

Golgi-impregnated and methionine-enkephalin (ME)- and substance P (SP)-immunoreactive neurons were studied throughout the feline nucleus tractus solitarii. The majority of Golgi-impregnated neurons in the NTS range in size from 5 to 18 micron. A noticeable exception is the large (15-30 micron) neurons of the ventrolateral subdivision. The Golgi-impregnated neurons possess dendritic trees which remain within the nucleus and even at times within the particular subdivisions. Golgi-impregnated neurons had a variety of spine forms: pedunculated, sessile, filiform, and complex. A number of neurons exhibited axons originating from the cell and they could be followed for distances up to 100 micron. ME- and SP-immunoreactive neurons were found in commissural, medial, lateral, and parvocellular subdivisions while ME-immunoreactive neurons were situated additionally in the intermediate and ventrolateral subdivisions. Both types of immunostained neurons were similar in size (6-20 micron) and shape of dendritic arbor. One population of ME-immunoreactive neurons resembled the large ventrolateral neurons of the Golgi impregnations. Neither type of immunostained neuron possessed the extensive dendritic arbor, numbers of spines, or axons of the Golgi-impregnated neurons. The presence of ME- and SP-immunoreactive neurons in regions which are associated with autonomic regulation suggests that these two peptides are involved in this process.

Animals↗
PubMed1983

Sympathoadrenal preganglionic neurons: their distribution and relationship to chemically-coded fibers in the kitten intermediolateral cell column.

The location of those sympathetic preganglionic neurons in the spinal cord that project to the adrenal medulla--the sympathoadrenal preganglionic (SAP) neurons--was studied by the method of retrograde axonal transport of the fluorescent dye Fast Blue. The distribution of chemically-coded fibers and their relationship to the SAP neurons was also investigated using the indirect immunofluorescence technique. In kittens, 5 microliters of a 1% solution of Fast Blue was injected into the medulla of the left adrenal gland. After a survival period of 5 days, the spinal cords from C8 to L5 were sectioned and processed for the localization of enkephalin-, neurophysin-, oxytocin-, serotonin-, substance P- and somatostatin-like immunoreactivity. Retrogradely labeled neurons were found in the ipsilateral intermediolateral cell column (IML) (89.8% of all retrogradely labeled neurons) from T1 to L4, and in the contralateral IML (10.2%) from T1 to L4. The enkephalin, serotonin and substance P immunoreactive fibers appeared to surround both the retrogradely labeled and unlabeled IML neurons. The somatostatin immunoreactive fibers were observed only in proximity to the retrogradely labeled neurons. Only a sparse population of neurophysin and oxytocin immunoreactive fibers were observed in IML, and were not seen to be in apposition to the retrogradely labeled neurons.

Adrenal Medulla↗