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PubMed1990

Distribution of neuropeptide Y in the prosencephalon of man and cotton-head tamarin (Saguinus oedipus): colocalization with somatostatin in neurons of striatum and amygdala.

The presence, chromatographic properties and localization of neuropeptide Y was demonstrated in postmortem human brain areas of neurologically and neuropsychiatrically normative controls using immunocytochemistry and high performance liquid chromatography combined with radioimmunoassay. NPY-immunoreactivity was found in many regions of the prosencephalon. Numerous perikarya and fibers were present in the neocortex, basal ganglia and limbic-hypothalamic areas. A moderate number of neurons and fibers was observed in the basal forebrain, including the septal complex. A comparative immunohistochemical investigation in perfusion-fixed brains of the old-world ape Saguinus oedipus revealed an almost identical distribution of NPY-immunoreactivity with only minor differences. Colocalization experiments on 1-2 microns thin consecutive paraffin sections revealed a large number of NPY neurons throughout the human neostriatum and amygdaloid complex that were also positive for somatostatin. Our findings indicate that detection of neuropeptides in fresh or fixed post-mortem human tissue by different immunochemical methods may actually reflect the in vivo conditions. In addition, the wide distribution of NPY throughout the human brain and its colocalization with other neurotransmitters suggests a physiological role as neuroactive substance, i.e. neuromodulator in the primate central nervous system.

Amygdala↗

PubMed1992

Colocalization of protein kinase C beta-subtype and calcitonin gene-related peptide in rat spinal cord.

Colocalization of calcitonin gene-related peptide (CGRP) and protein kinase C beta-subtype (PKC-beta) like immunoreactivities (LI) and the subcellular localization of CGRP-LI were studied in the ventral horn of rat spinal cord. Ultrastructurally CGRP-LI was localized on the membranes of the Golgi-complexes, in multivesicular bodies and in vesicles adjacent to the Golgi-complex in motoneuron perikarya. The colocalization of PKC-beta and CGRP-LI was detected in most of the ventral horn motoneurons. However, few motoneurons were only PKC-beta-immunoreactive. These results suggest that PKC-beta may be involved in the regulation of CGRP release from motoric axon terminals.

Animals↗

PubMed1992

Some peptide-like colocalizations in endocrine cells of the pyloric caeca and the intestine of Oncorhynchus mykiss (Teleostei).

The coexistence of immunoreactivities to cholecystokinin, glucagon, glucagon-like peptide 1, salmon pancreatic polypeptide, neuropeptide tyrosine, and peptide tyrosine tyrosine was studied immunocytochemically, revealing for the first time in fish intestine the existence in the same cell of immunoreactivities to cholecystokinin-glucagon/glucagon-like peptide 1, cholecystokinin-salmon pancreatic polypeptide, glucagon/glucagon-like peptide 1-salmon pancreatic polypeptide, glucagon/glucagon-like peptide 1-neuropeptide tyrosine, salmon pancreatic polypeptide tyrosine tyrosine, and glucagon/glucagon-like peptide 1-peptide tyrosine tyrosine. Colocalization of cholecystokinin-salmon pancreatic polypeptide was observed only in the pyloric caeca of the rainbow trout Oncorhynchus mykiss, while the other colocalizations also occurred in proximal and middle intestinal segments. In all cases, endocrine cells immunoreactive to only one of the paired antisera were detected except for anti-glucagon and anti-glucagon-like peptide 1, which always immunostained the same cells.

Animals↗

PubMed1987

Colocalization of (3H)-adenosine accumulation and GABA immunoreactivity in the chicken and rabbit retinas.

Using combined autoradiography and immunohistochemistry, we have compared (3H)-adenosine accumulation and GABA immunoreactivity in the chicken and rabbit retinas. Colocalization of the two markers was observed in a subset of amacrine cells and in certain cell bodies in the ganglion cell layer in both species and in a few horizontal cells in the chicken retina. Cells that contained only (3H)-adenosine or GABA were also seen. The degree of colocalization differed greatly between the two species. The results demonstrate a morphological relationship between the adenosine and GABA systems and provides information on the possible anatomical substrates underlying at least some types of functional interactions.

Adenosine↗

PubMed1985

Corticotropin-releasing factor: immunohistochemical colocalization with adrenocorticotropin and beta-endorphin, but not with Met-enkephalin, in subpopulations of duodenal perikarya of rat.

By the use of two different double-staining techniques (simultaneous staining of adjacent serial sections and the double-staining elution method) it was possible to demonstrate that a corticotropin-releasing factor (CRF) immunofluorescence co-existed with an adrenocorticotropin (ACTH) and beta-endorphin (beta-END) immunoreactivity, but not with a Met-enkephalin (Met-ENK) immunostaining, within perikarya subpopulations of both the myenteric and submucousal plexus of the rat duodenum. Not a single Met-ENK-positive neuronal cell body was stained also for CRF, ACTH or beta-END. Even nerve fibres, localized in both the myenteric plexus and closely to submucousal blood vessels (probably arterioles), revealed a CRF immunofluorescence, which is also colocalized with an beta-END staining. These results are quite different to the recent observations in the mammalian hypothalamus, suggesting that some myenteric and submucousal plexus neurons may synthesize CRF as well as beta-END and ACTH, but not Met-ENK. The colocalized peptides might be concomitantly released into the synaptic cleft after terminal stimulation.

Adrenocorticotropic Hormone↗

PubMed1988

Extent of colocalization of serotonin and GABA in neurons of the ventral medulla oblongata in rat.

The colocalization of serotonin (5-hydroxytryptamine; 5-HT) and gamma-aminobutyric acid (GABA) in the ventral aspect of the rat medulla oblongata was studied using antibodies directed against 5-HT and GABA. Although 5-HT- and GABA-immunoreactive cell bodies were observed over the entire rostral-caudal extent of the ventral medulla, the colocalization of these two classical neurotransmitters in single cells was, for the most part, limited to a region that corresponds anatomically to nucleus raphe magnus/nucleus paragigantocellularis. Schematic drawings showing the distribution of 5-HT/GABA cell bodies in the ventral medulla are provided.

Animals↗

PubMed1988

Colocalization of glycine-like and GABA-like immunoreactivities in Golgi cell terminals in the rat cerebellum: a postembedding light and electron microscopic study.

Consecutive sections of rat cerebella were incubated with antisera raised against glycine or gamma-aminobutyric acid (GABA) conjugated to protein by glutaraldehyde. The sections were subsequently processed according to the peroxidase-antiperoxidase technique (semithin sections) or treated with a secondary antibody coupled to colloidal gold particles (ultrathin sections). Corroborating previous light microscopic observations based on pre-embedding immunocytochemistry, a major proportion (about 70%) of the Golgi cell bodies showed immunoreactivity for both glycine and GABA. Analyses of semithin sections further suggested that the two immunoreactivities were colocalized in the same glomeruli and even in the same Golgi cell terminals. This was confirmed by electron microscopy. Quantification of the immunogold labelling for glycine (which is assumed to play metabolic roles in addition to its presumed role as a transmitter) showed that the net gold particle density was an order of magnitude higher over Golgi cell terminals than over the other constituents of the cerebellar glomeruli (mossy fibre terminals and granule cell dendrites). The total particle density over the latter was only slightly higher than the background level (over empty resin), suggesting that the concentration of 'metabolic' glycine is generally low compared to the concentration of glycine in Golgi cells. The stellate and basket cell terminals (which similarly to the Golgi cells are thought to release GABA as transmitter) were immunoreactive for GABA, but (with very few exceptions) virtually unlabelled for glycine, suggesting that our results were not confounded by any crossreactivity of the glycine antiserum with fixed GABA. Direct evidence that the sera reacted selectively with fixed glycine or GABA under the conditions used was obtained by incubating the tissue sections together with test sections containing a series of different amino acid-glutaraldehyde-brain macromolecule conjugates. Adsorption tests with soluble amino acid-glutaraldehyde complexes similarly suggested that the double-labelling of the Golgi terminals indeed reflected a colocalization of glycine and GABA. The results show that two 'classical' transmitters, both being inhibitory and acting on Cl- channels, may coexist in the same nerve terminals.

Animals↗

PubMed1990

Microangiopathy and the colocalization of heparan sulfate proteoglycan with amyloid in senile plaques of Alzheimer's disease.

While the pathogenetic mechanisms responsible for Alzheimer's Disease (AD) remain unknown, blood vessel deformities, thickened vascular basement membrane (VBM), and amyloid fibrils emanating from the VBM all suggest vascular involvement. The present study immunocytochemically localized the VBM constituent heparan sulfate proteoglycan (HSPG), which is said to play a role in filtration of anionic and neutral proteins. In addition, thioflavine S was used to double-label each tissue section for the presence of amyloid. Samples were taken from frontal, temporal and parietal lobes of 8 patients who exhibited the neuropathologic lesions of AD and 6 patients who did not. HSPG immunolabeled the capillary bed in all samples. Tissue from patients with AD, however, exhibited severe microangiopathic changes: ragged and irregular outer capillary walls, both thickened and attenuated capillary diameters, and regionally increased capillary density. In addition, plaque-like extravascular accumulations of HSPG were seen in all patients with AD. These accumulations were found in the vicinity of capillaries, and were commonly colocalized with amyloid. Neither extravascular clouds of HSPG immunoreactivity nor fluorescing accumulations of amyloid were found in non-AD patients. The pattern of HSPG immunostaining confirms: (1) the high incidence of microangiopathy in AD; (2) the close anatomic relationship between plaque constituents and capillaries; and (3) the colocalization of HSPG with extravascular amyloid. The cerebral vasculature, and specifically the VBM, may thus be actively involved in the pathogenesis of AD.

Aged↗

PubMed1991

Incorporation of circulating fibronectin into various tissues during sepsis: colocalization with endogenous tissue fibronectin.

We studied the plasma clearance and tissue incorporation of intravenously infused purified human plasma fibronectin into various tissues during a period of acute lung vascular injury induced by lethal postoperative bacteremia in sheep. Lung, liver, spleen, and heart tissue were examined for both endogenous sheep tissue fibronectin as well as the experimentally infused human fibronectin using dual-label immunofluorescence. Awake sheep (n = 4) received a postoperative iv infusion of 5 x 10(9) live Pseudomonas over a 60-min infusion interval. Bacterial challenge was started 2 hr after starting the iv fibronectin infusion of purified human plasma fibronectin (100 mg iv bolus; 4 hr iv at 100 mg/hr). Human fibronectin displayed a biphasic rate of clearance from the plasma with entrance into lymph. Human fibronectin readily incorporated in all tissues studied, including the lung which was the focus of vascular injury. Analysis of tissue sections by dual-label immunofluorescence indicated that the exogenous human fibronectin colocalized with the endogenous sheep fibronectin. Thus, the plasma fibronectin concentration may influence the lung vascular barrier due to its incorporation into the tissue pool of fibronectin. Moreover, the plasma may serve as a reservoir for soluble fibronectin which can enter and colocalize with the insoluble tissue pool of fibronectin in various tissues.

Animals↗

PubMed1989

Internalized ricin and the plasma membrane glycoprotein MAM-6 colocalize in the trans-Golgi network of T47D human breast carcinoma cells.

We have analyzed the intracellular transport of endocytosed ricin in the human breast carcinoma cell line T47D. Cells were incubated with ricin (10 micrograms/ml) for 1 h at 37 degrees C. Marked reduction in the protein synthesis did not take place until the end of this period. To detect ricin immunocytochemically, a rabbit anti-ricin serum was used. Gel electrophoresis followed by immunoblotting revealed that the antiserum reacted specifically with ricin and detected both the ricin A-chain and the ricin B-chain. Immunofluorescence experiments showed endocytosed ricin in endosomal and lysosomal vacuoles throughout the cytoplasm, as well as in a typical perinuclear position corresponding to the Golgi region. Using the monoclonal mouse antibody 115D8 directed toward the high-molecular-weight membrane glycoprotein MAM-6 of human breast epithelial cells, we similarly obtained a swarms of small vesicles throughout the cytoplasm. To further analyze the apparent colocalization of ricin and MAM-6 in the perinuclear Golgi region, immunogold cytochemistry on ultracryosections was performed. MAM-6 was detected mainly in Golgi stacks and associated trans-Golgi network (TGN) profiles, in 0.1 to 0.2-micron secretory vesicles, and on the cell surface. Ricin was detected on the cell surface, in endosomes and lysosomes, and also in the TGN. Furthermore, by using immunogold double labeling, internalized ricin was found to colocalize with MAM-6 in the TGN.

Antibodies, Monoclonal↗

PubMed1990

Colocalized peptides in gonadotrophs: LeuEnkephalin and ACTH interact differently on GnRH induced LH and FSH release.

Two peptides that have been previously colocalized in the gonadotrops (LeuEnkephalin with LH and ACTH with FSH) can stimulate the release of gonadotropins in primary culture of anterior pituitary cells. In presence of both substances, and in contrast to LHRH induced secretion, the augmentation of LH release is never dose dependent. It is always significantly higher than controls, for high (10(-6) M) or low concentrations (10(-12) M). Prolactin release is only modified in presence of Leu-Enkephalin. Met-Enkephalin does not increase the liberation of LH, FSH, or Prolactin in vitro. Furthermore, while Leu-Enkephalin can enhance the stimulating effect of LHRH, ACTH has a negative interaction with LHRH, when these two peptides are added together in incubation medium. These results demonstrate that Leu-Enkephalin and ACTH can in vitro modulate the release of gonadotrophins at the pituitary level suggesting a physiological role for such colocalization.

Adrenocorticotropic Hormone↗

PubMed1991

Calcitonin and calcitonin gene-related peptide immunoreactivity and colocalization in newborn cat lung.

Calcitonin (CT) and calcitonin gene-related peptide (CGRP) are generated by alternate RNA processing from alpha and beta CT/CGRP genes. In this report, an immunocytochemical investigation was undertaken on the occurrence and distribution of immunoreactive CT as well as its colocalization with CGRP in newborn cat bronchopulmonary endocrine cells. A widespread distribution of solitary endocrine cells and neuroepithelial bodies immunostained for CT was recorded within the lung. In all animals studied, CT immunoreactivity represents a subpopulation of CGRP positive cells, while the intrapulmonary nerve fibers contain only CGRP. To the best of our knowledge, this is the first time that CT and its colocalization with CGRP have been demonstrated immunocytochemically in the cat lung. Our results indicate, that different molecular processing of both CT/CGRP genes may be represented by different patterns in the cellular immunoreactivity of the synthetized peptides.

Animals↗

PubMed1991

Dynorphin expression and Fos-like immunoreactivity following inflammation induced hyperalgesia are colocalized in spinal cord neurons.

Fos and Fos-related proteins are increased in spinal dorsal horn neurons following noxious stimulation. The laminar location of neurons that exhibit this increase is coincident with those that exhibit an increase in dynorphin in a rat model of peripheral inflammation and hyperalgesia. In order to determine whether the increase in Fos or related proteins and dynorphin occurs in the same dorsal horn neurons, two kinds of double-labeling methods were used: in situ hybridization histochemistry to label dynorphin mRNA autoradiographically, and immunocytochemistry to label Fos and Fos-related proteins, or a double immunocytochemical method that labeled Fos and Fos-related proteins and dynorphin peptide with distinct chromagens. With both methods more than 80% of the neurons in laminae I, II, V and VI exhibiting an increase in either dynorphin mRNA or peptide following peripheral inflammation also colocalized increased nuclear Fos-like immunoreactivity. However, the number of neurons displaying increased Fos-like immunoreactivity was substantially greater than the number of neurons colocalizing increased dynorphin. These data suggest that the activation of nuclear Fos and Fos-related proteins may be related to the induction of dynorphin gene expression in a subpopulation of spinal cord neurons following peripheral inflammation and hyperalgesia.

Animals↗

PubMedDate not supplied

Substance P and neurokinin A are codistributed and colocalized in the porcine gastrointestinal tract.

Immunoreactive substance P and neurokinin A were measured with radioimmunoassay in extracts of different segments of porcine gastrointestinal tract using C-terminally directed antisera. In all segments, the concentrations of substance P and neurokinin A were similar. The largest concentrations of both peptides were found in the mid-colon. By gel chromatography and reversed-phase high pressure liquid chromatography the immunoreactivity in extracts from ileum eluted as homogenous peptides at the positions of synthetic substance P and neurokinin A, respectively. No neurokinin B was found. By immunohistochemistry of porcine duodenum, jejunum, ileum and mid-colon, identical localization patterns were found for substance P and neurokinin A, and the two peptides demonstrated by double immunofluorescence to be colocalized in the enteric nervous system of the ileum. We conclude that the tachykinins substance P and neurokinin A are codistributed and colocalized in the procine gastrointestinal tract and suggest that the two peptides are produced from a common precursor, beta- and/or gamma-preprotachykinin, in the same neurons.

Animals↗

PubMedDate not supplied

Colocalization of endothelin, vasopressin and serotonin in cultured endothelial cells of rabbit aorta.

The localization and colocalization of endothelin-1, arginine-vasopressin and serotonin in the endothelial cells of rabbit aorta in primary culture were investigated by preembedding and postembedding immunocytochemistry. These three substances were localized in the same population of cells, where they appeared in high proportions (greater than 60%). These findings indicate: 1) that the cell population is heterogeneous, and 2) that these substances are colocalized in some of the cultured endothelial cells. Double labeling in single cells has demonstrated the simultaneous presence of 1) endothelin and vasopressin, 2) vasopressin and serotonin, and 3) endothelin and serotonin. The immunolabeling dominated in the cytoplasmic matrix.

Animals↗

PubMed1987

Colocalization of GABA and tyrosine hydroxylase immunoreactivities in the axons innervating the neurointermediate lobe of the rat pituitary: an ultrastructural immunogold study.

Distribution of the gamma-aminobutyric acid (GABA)ergic and dopaminergic innervations was studied in the rat neurointermediate lobe using antibodies against GABA and tyrosine hydroxylase. In light microscopy, immunoperoxidase staining revealed similar distribution patterns of the axons reacting with both antibodies. Diffusely scattered in both lobes, they were more concentrated along the marginal zone of the neural lobe. Application of a double, recto-verso, immunogold labelling method in electron microscopy revealed systematic colocalization of GABA and tyrosine hydroxylase (TH) immunoreactivities in the axons innervating the intermediate lobe; in the neural lobe, almost all GABA-immunoreactive axons were also labelled for TH. Thus, GABA and dopamine, hitherto reported to occur in distinct axons, in fact colocalize in the axonal systems which innervate the pituitary neurointermediate lobe. These observations suggest possible interactions (pre- or postsynaptic) of both transmitters in the functional regulation of the intermediate and neural lobes.

Animals↗

PubMed1989

Evidence for colocalization of substance P and 5-hydroxytryptamine in spinally projecting neurons from the cat medulla oblongata.

Substance P (SP)- and 5-hydroxytryptamine (5-HT)-like immunoreactivities were localized in bulbospinal neurons of the raphe nuclei and ventrolateral medulla (VLM). In raphe pallidus and raphe obscurus virtually all of the spinally projecting neurons contained SP and/or 5-HT. Furthermore, SP and 5-HT were colocalized in half of these spinal-raphe neurons. In raphe magnus few spinally projecting neurons contained either SP or 5-HT. Half of the bulbospinal neurons in the caudal VLM contained SP and/or 5-HT and in 50% of these SP and 5-HT were colocalized. However, no SP-containing neurons in the rostral VLM projected to the spinal cord.

Animals↗

PubMed1989

The colocalization of cholecystokinin and tyrosine hydroxylase mRNAs in mesencephalic dopaminergic neurons in the rat brain examined by in situ hybridization.

The colocalization of cholecystokinin and tyrosine hydroxylase mRNAs was studied with a cellular resolution in the mesencephalic dopaminergic neurons of the rat brain by in situ hybridization using synthetic oligonucleotides. An extensive colocalization of cholecystokinin-expressing cells, greater than that seen previously by immunohistochemistry, was found in the ventral tegmental area and in the substantia nigra pars compacta. We observed in these regions that cholecystokinin and tyrosine hydroxylase mRNAs coexisted in the same neurons but not all dopamine cells expressed cholecystokinin mRNA. 6-Hydroxydopamine-induced destruction of mesostriatal dopaminergic neurons resulted in a complete loss of cholecystokinin and tyrosine hydroxylase mRNA expression throughout the substantia nigra pars compacta, indicating that all cholecystokinin expressing cells are 6-hydroxydopamine-sensitive. While increased enkephalin mRNA expression in the striatum ipsilateral to the lesion was detected, no change of cholecystokinin mRNA expression was observed in any forebrain on the lesioned side, suggesting that cholecystokinin expression in the forebrain is not under dopaminergic control. These results show the usefulness of the in situ hybridization approach for the precise localization of cells in rat brain which express mRNAs for cholecystokinin and tyrosine hydroxylase and for the study of the effects of neurotoxic lesions on these cells.

Animals↗