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E Brodin

Publications and source records attributed to E Brodin.

At least 91 records · Page 5Linked to original sources
PubMed1987

Sample handling techniques when analyzing regulatory peptides.

Collection of blood samples in prechilled heparinized tubes, rapid cooling and centrifugation at 4 degrees C were found to be more important than the enzyme inhibitors aprotinin and EDTA in preserving immunoreactive neuropeptide Y. Nine months after storage of plasma in the frozen state at -20 degrees C or -80 degrees C the recovery of NPY was about 50% of the recovery at immediate analysis. Synthetic substance P added to guinea pig plasma at 37 degrees C disappeared almost entirely within 30 seconds as measured by radioimmunoassay while the concentrations of neurokinin A and neuropeptide K decreased only to a minor extent during a 20 min observation period. The total concentration of immunoreactive substance P and neurokinin A in boiled aqueous and acetic acid extracts of rat dorsal spinal cord was on the other hand stable for 72 h at 4 degrees C, 24 h at room temperature and after freezing and thawing three times. However, chromatographic analysis indicated that the immunoreactivity became increasingly more heterogenous in the samples particularily at room temperature. Acid ethanol and Sep Pak extraction of plasma samples resulted in almost 90% recovery of neuropeptide Y, neuropeptide K and calcitonin gene-related peptide while removing crossreacting substances with high molecular weight.

Animals↗
PubMed1987

In vivo release of substance P in cat dorsal horn studied with microdialysis.

Variations in the extracellular concentration of substance P (SP) were measured in cat dorsal horn in vivo by microdialysis and radioimmunoassay. Electrical unilateral stimulation of the sciatic nerve was used to evoke release of SP. At high-intensity stimulation, activating slowly conducting (approx. 0.9 m/s) fibres, there was an increase in substance P-like immunoreactivity (SP-LI) to 338% of the preceding control value (P less than 0.05, n = 5) in the dialysates collected at levels L6-L7 at the stimulated side. A less pronounced increase, to 164% of the basal level, was found at the contralateral side. More cranially (L1-L5) in the dorsal horn at the stimulated side, only a moderate or no increase in SP-LI was seen. Stimulation with low intensity, sufficient to activate fast (greater than 20 m/s), but not slowly conducting fibres, evoked no increase in SP-LI. The results indicate that unilateral peripheral C-fibre activation induces a local SP release in the dorsal horn present also on the side not stimulated.

Action Potentials↗
PubMed1987

Primary sensory neurons of the rat showing calcitonin gene-related peptide immunoreactivity and their relation to substance P-, somatostatin-, galanin-, vasoactive intestinal polypeptide- and cholecystokinin-immunoreactive ganglion cells.

By use of the indirect immunofluorescence technique the distribution of calcitonin gene-related peptide (CGRP)-like immunoreactivity (LI) has been analyzed in cervical and lumbar dorsal root ganglia of untreated and colchicine-treated rats. In addition, lumbar ganglia were examined 2 weeks after transection of the sciatic nerve. The occurrence of CGRP-positive cells in relation to ganglion cells containing substance P-, somatostatin-, galanin-, cholecystokinin (CCK)-, and vasoactive intestinal polypeptide (VIP)/peptide histidine isoleucin (PHI)-LI has been evaluated on consecutive sections as well as using elution-restaining and double-staining techniques. CGRP-LI was observed in many ganglion cells of all sizes ranging in diameter from 15 microns to 65 microns. Thus, this peptide occurs also in the large primary sensory neurons. In contrast to the sensory peptides described to date, CGRP-positive cells constituted up to 50% of all and 70% of the medium-sized neurons, thus being the most frequently occurring peptide in sensory neurons so far encountered. Subpulations of CGRP-positive neurons were shown to contain substance P-, somatostatin-, or galanin-LI and some CGRP-positive neurons contained both substance P- and galanin-LI. In fact, most substance P-, somatostatin- and galanin-positive cell bodies were CGRP-immunoreactive. The coexistence analysis further revealed that galanin and substance P often coexisted and that some cells contained both substance P- and somatostatin-LI, whereas no coexistence between galanin and somatostatin has as yet been seen. VIP/PHI-LI was only shown in a few cells in untreated or colchicine-treated rats. However, after transection of the sciatic nerve numerous VIP/PHI-positive cells were observed, some of which also contained CGRP-LI. The present results indicate that a CGRP-like peptide is present in a wide range of primary sensory neurons probably not related to specific sensory modalities. Often this peptide coexists with other biologically active peptides. Taken together these findings suggest that CGRP may have a generalized function.

Animals↗
PubMed1987

Effects of subchronic treatment with imipramine, zimelidine and alaproclate on regional tissue levels of substance P- and neurokinin A/neurokinin B-like immunoreactivity in the brain and spinal cord of the rat.

The effects of subchronic (14 day) treatment with the inhibitors at the uptake of monoamines, zimelidine, alaproclate and imipramine, on regional levels of substance P (SP) and other tachykinins in tissue in the central nervous system of the rat were studied by radioimmunoassay. In the ventral spinal cord, in which substance P is known to exist together with 5-hydroxytryptamine (5-HT), in the terminals of descending neurones, treatment with the selective inhibitors of the uptake of 5-HT zimelidine (2 X 10 mumol/kg p.o.) or alaproclate (2 X 10 mumol/kg or 2 X 20 mumol/kg p.o.), increased the level of substance P-like immunoreactivity (SP-LI). The effect of alaproclate appeared to be dose-dependent. After treatment with imipramine (2 X 10 mumol/kg p.o.) only a tendency to increased levels of substance P-like immunoreactivity spinal cord was seen. Treatment with alaproclate, at the highest dose level, also elevated the concentration of neurokinin A/neurokinin B-like immunoreactivity (NKA/NKB-LI) in the ventral spinal cord. In the frontal cortex, in which separate monoaminergic and tachykinin-containing neurones interact, treatment with imipramine reduced the levels of SP-LI and NKA/NKB-LI, while treatment with alaproclate had the opposite effect. In the periaqueductal grey matter, treatment with zimelidine and alaproclate increased the levels of SP-LI and NKA/NKB-LI, while treatment with imipramine increased only the level of NKA/NKB-LI. In conclusion, subchronic treatment of rats with inhibitors of the uptake of monoamines induced changes in levels of tachykinin in frontal cortex, periaqueductal grey and spinal cord. The selective inhibitors of the uptake zimelidine and alaproclate, had similar effects on levels of tachykinin, while the inhibitor of the uptake of 5-HT and noradrenaline, imipramine induced changes in the frontal cortex, which were qualitatively different from the effects of zimelidine and alaproclate. Furthermore, the levels of different tachykinins were not always changed in parallel by the same treatment.

Alanine↗
PubMed1987

Microdialysis combined with a sensitive radioimmunoassay. A technique for studying in vivo release of neuropeptides.

Microdialysis in combination with radioimmunoassay was used to study in vivo release of neuropeptides in the rat brain. Microdialysis is a novel brain perfusion technique, by which molecules in the extracellular space may be monitored. This study describes the application to neuropeptide research. A radioimmunoassay procedure was adapted so that substance P- and neurokinin A-like immunoreactivity could be measured in samples collected during in vivo release experiments. The detection limits of substance P and neurokinin A were below 0.1 fmol/100-microliters sample and the IC50 approximately 1 fmol/sample for both peptides. Potassium, introduced via the microdialysis probe, was found to induce a concentration-dependent increase of the extracellular concentration of neurokinin A-like immunoreactivity.

Animals↗
PubMed1987

Analysis of peptide histidine-isoleucine/vasoactive intestinal polypeptide-immunoreactive neurons in the central nervous system with special reference to their relation to corticotropin releasing factor- and enkephalin-like immunoreactivities in the paraventricular hypothalamic nucleus.

The distribution of peptide histidine-isoleucine (PHI) and vasoactive intestinal polypeptide (VIP), two peptides derived from the same precursor molecule, was analysed with immunohistochemistry in the central nervous system of the rat, and to a limited extent in some other species including sheep, monkey and man. Special attention was focused on possible cross-reactivity between PHI antisera and corticotropin releasing factor in parvocellular neurons in the hypothalamic paraventricular nucleus projecting to the external layer of the median eminence. (1) Characterization of the PHI and VIP antisera revealed that they recognized different sequences of the peptide molecules. One of the PHI antisera (PHI-N), although mainly N-terminally directed, also probably contained an antibody population directed against the C-terminal amino acid in PHI which is an amidated isoleucine. Rat and human corticotropin releasing factor but not ovine also have an amidated isoleucine in C-terminal position. (2) PHI- and VIP-like immunoreactivity were found with parallel and overlapping distribution in all areas investigated in the rat central nervous system. In many cases coexistence of the two immunoreactivities could be directly demonstrated. PHI neurons were found in some areas so far not know to contain PHI/VIP neurons, including the dorsal septum, the septofimbrial nucleus, the stria terminalis and lamina V of the spinal cord. (3) Using an antiserum directed against the amino acid sequence 111-122 of the VIP/PHI precursor, immunoreactive cell bodies were seen in some areas containing VIP and PHI neurons. PHI- and VIP-like immunoreactivity were expressed in parallel in increasing amounts in the superficial laminae of the dorsal horn after transection of the sciatic nerve [G. P. McGregor et al. (1984) Neuroscience 13, 207-216; S. A. S. Shehab and M. E. Atkinson (1984) J. Anat. 139, 725; S. A. S. Shehab and M. E. Atkinson (1986) Expl Brain Res. 62, 422-430]. (5) The PHI-N antiserum stains large numbers of immunoreactive cells in the parvocellular part of the paraventricular nucleus and these cells are mostly identical with corticotropin releasing factor-positive neurons. Absorption experiments suggested that this PHI-N-like immunoreactivity to a large extent represented cross-reactivity with rat CRF and that earlier demonstration of many PHI-positive neurons in the paraventricular nucleus probably represents an artefact as proposed by F. Berkenbosch et al. (Neuroendocrinology 44, 338-346). However, some cells did, in fact, contain VIP- as well as PHI-like immunoreactivity as was shown with antisera not cross-reacting with corticotropin releasing factor.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1987

An ultrastructural study of 5-hydroxytryptamine-, thyrotropin-releasing hormone- and substance P-immunoreactive axonal boutons in the motor nucleus of spinal cord segments L7-S1 in the adult cat.

The distribution and fine structure of 5-hydroxytryptamine-, thyrotropin-releasing hormone- and substance P-immunoreactive synaptic boutons and varicosities were studied in the motor nucleus of the spinal cord segments L7-S1 in the cat, using the peroxidase-antiperoxidase immunohistochemical technique and analysis of ultrathin serial sections. The 5-hydroxytryptamine-, thyrotropin-releasing hormone- and substance P-immunoreactive boutons had a similar ultrastructural appearance as judged from serial section analysis. The boutons could be classified into two types on the basis of their vesicular content, with one type containing a large number of small agranular vesicles together with only a few, if any large granular vesicles, while the other type contained a large number of large granular vesicles in addition to small agranular vesicles. The vesicles were spherical or spherical-to-pleomorphic. Postsynaptic dense bodies (Taxi bodies) were occasionally observed in relation to all three types of immunoreactive boutons, which almost invariably formed synaptic junctions with dendrites. Judged by the calibre of the postsynaptic dendrites, the boutons were preferentially distributed to the proximal dendritic domains of motoneurons. In one case, a substance P-immunoreactive bouton formed an axosomatic synaptic contact. In addition to synaptic boutons, 5-hydroxytryptamine-, thyrotropin-releasing hormone- and substance P-immunoreactive axonal varicosities containing a large number of large granular and small agranular vesicles but lacking any form of conventional synaptic contact were observed. Such varicosities were either directly apposing surrounding neuronal elements or separated from the neurons by thin glial processes. The origin of the immunoreactive boutons was not traced, but it was thought likely that the main source of the boutons was neurons with their cell bodies located in the medullary raphe nuclei.

Animals↗
PubMed1987

Sensory neuropeptides contribute to oedema formation in experimental burns.

The role of primary sensory neuropeptides in experimental burns was investigated. It was shown that after scalding, substance P-like immunoreactivity is released into the lymphatic fluid of dogs. Substance P, injected intravenously, was shown to cause dose-dependent oedema formation in rat skin, as measured with the Evans blue-technique. Furthermore, capsaicin pretreatment, which depletes the neuropeptide content of primary sensory neurons, was shown to inhibit late oedema formation in rats.

Animals↗
PubMed1986

In vivo release of substance P in the nucleus tractus solitarii increases during hypoxia.

In vivo release of substance P (SP) was measured by microdialysis in the nucleus tractus solitarii (nTS) in adult cats. Small perfused semipermeable tubules (microdialysis probes) were implanted stereotaxically in the nTS, at the position of respiration-related neurons and perfused with artificial CSF. SP was determined by radioimmunoassay of the perfusate. Increased extracellular concentrations of SP-like immunoreactivity (SP-LI) were measured during hypoxia induced in artificially ventilated cats. In addition, a prolonged increase in the extracellular SP-LI concentration was encountered after cervical vagotomy. The results corroborate the suggestion that SP is a mediator of the central response to hypoxia.

Animals↗
PubMed1986

Neuropeptide Y, enkephalin and noradrenaline coexist in sympathetic neurons innervating the bovine spleen. Biochemical and immunohistochemical evidence.

The subcellular distribution of noradrenaline (NA), neuropeptide Y (NPY), Met- and Leu-enkephalin (ENK), substance P (SP), somatostatin (SOM), and vasoactive intestinal polypeptide (VIP) was investigated in homogenates of bovine splenic nerve. The distribution of noradrenergic peptide-containing nerves in the bovine celiac ganglion, splenic nerve and terminal areas in spleen was studied by indirect immunofluorescence histochemistry using antisera to tyrosine hydroxylase (TH), dopamine-beta-hydroxylase (DBH), NPY, enkephalin peptides, SP, SOM, VIP, and peptide HI (PHI). After density gradient centrifugation, high levels of NPY- and ENK-like immunoreactivity (LI) were found in high-density gradient fractions, coinciding with the main NA peak. SP, SOM and VIP were found in fractions with a lower density, VIP being also enriched in a heavy fraction; the latter three peptides were present in low concentrations. Immunohistochemistry revealed that staining for NPY-LI and ENK-LI partly overlapped that for TH and DBH in celiac ganglia, splenic nerve axons and terminal areas of spleen. Almost all principal ganglion cells were TH- and DBH-immunoreactive. Many were also NPY-immunoreactive, whereas a smaller number were ENK-positive. In the celiac ganglion patches of dense SP-positive networks and some VIP/PHI- and ENK-immunoreactive fibers were seen around cell bodies. The results indicate that NPY and ENK are stored with NA in large dense-cored vesicles in unmyelinated axons of bovine splenic nerve. SP, SOM and VIP appear in different organelles in axon populations separate from sympathetic noradrenergic nerves.

Adrenergic Fibers↗
PubMed1986

Serotonin type-2 receptor mediated regulation of substance P release in the ventral spinal cord and the effects of chronic antidepressant treatment.

Regulation of the release of substance P (SP) by the coexisting neurotransmitter serotonin (5-hydroxytryptamine, 5-HT) in the ventral spinal cord and the effects of chronic antidepressant treatment mediated changes in serotonin metabolism on the regulation, were examined. The K+ (40 mmol/l) evoked release of (SP) from slices of the ventral spinal cord of the rat was potentiated by (5-HT) applied to 100 mumol/l concentration. This effect was blocked by the serotoninergic antagonists methysergide (10 mumol/l), methiotepin (10 mumol/l) and fully blocked by ketanserin (10 mumol/l). Thus the 5-HT receptor which regulates the release of SP appears to belong to the type-2 5-HT receptors. Chronic treatment with the selective serotonin uptake inhibitor zimelidine (14 days, 2 X 10 mumol/kg/day, p.o.) lowered the tissue levels of the 5-HT metabolite: 5-hydroxyindol acetic acid (5-HIAA) and elevated the tissue levels of SP in both the ventral and dorsal spinal cord as compared to that in the vehicle treated group (14 days, 2 X 5 ml saline/kg/day, p.o.). The decrease in the 5-HIAA levels after chronic zimelidine treatment was quantitatively similar in the dorsal (33%, p less than 0.01) and ventral (31%, p less than 0.05) spinal cord. The increase in SP levels after chronic zimelidine treatment was more pronounced in the ventral cord (80%, p less than 0.01) where the majority of the SP containing nerve endings also contain 5-HT, than in the dorsal spinal cord (22% increase in SP, p less than 0.05), where only a minor fraction of the SP-containing nerve endings shows a 5-HT/SP coexistence.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1986

Neuroleptic treatment induces region-specific changes in levels of neurokinin A and substance P in rat brain.

The effects of 10 days treatment with haloperidol or sulpiride on tissue levels of neurokinin A-like and substance P-like immunoreactivity (NKA-LI and SP-LI) in various regions of rat brain were studied using reversed phase HPLC and radioimmunoassay. The most marked effect was a decrease in NKA-LI levels in n.accumbens after treatment with both sulpiride and haloperidol. Striatal NKA-LI and SP-LI levels were not clearly affected. NKA-LI levels but not SP-LI levels were decreased in substantia nigra by haloperidol. A low dose of sulpiride increased both NKA-LI and SP-LI levels in ventral tegmental area/n.interpeduncularis. In conclusion, region-specific changes of NKA-LI and SP-LI were seen after subchronic treatment with neuroleptics. It seems likely that NKA and SP are involved in the neuronal adaptation to the repeated treatment with neuroleptics.

Animals↗
PubMed1986

Tachykinin multiplicity in rat central nervous system as studied using antisera raised against substance P and neurokinin A.

Antisera were raised in rabbits against the tachykinins neurokinin A (NKA) and substance P (SP). All NKA-antisera tested cross-reacted markedly with NKB, kassinin and eledoisin in radioimmunoassay (RIA), but virtually not with SP and physalaemin. Also when used for immunohistochemistry, one of the NKA-antisera was found to be virtually without cross-reactivity with SP. The most specific SP-antiserum did not cross-react with NKA but to some extent with NKB at the immunohistochemical level. Using these two antisera, the same distribution pattern of immunoreactivity was seen in both the rat substantia nigra and dorsal spinal cord. In neutral extracts of the substantia nigra, all NKA-antisera used for RIA detected a major component which eluted at the position of NKA in reverse phase high performance liquid chromatography, while no or only little immunoreactivity was detected at the position of NKB. A major component of substance P-like immunoreactivity (SPLI) co-eluting with SP and one or two minor SPLI-components were also detected in these extracts. An SP-antiserum, which cross-reacted markedly with physalaemin, detected an additional rather prominent component. In neutral water extracts of dorsal spinal cord the component detected with the NKA-antisera at the position of NKB, as well as one of the SPLI-components not eluting in the position of SP, were much more prominent than in the corresponding extracts of substantia nigra. In acetic acid extracts of both tissues, only one major SPLI-component co-eluting with SP could be detected, while only very small amounts of immunoreactivity eluting at the position of NKA and NKB (dorsal spinal cord only) could be detected using the NKA-antisera. The present results illustrate the importance of the extraction method used in immunochemical studies and demonstrate that the relative proportions of various tachykinins are markedly different in the rat substantia nigra and dorsal spinal cord.

Animals↗
PubMed1986

Capsaicin induced release of multiple tachykinins (substance P, neurokinin A and eledoisin-like material) from guinea-pig spinal cord and ureter.

The release of tachykinins from isolated slice preparations of the guinea-pig spinal cord and ureter was studied in vitro. Capsaicin (10 microM) caused release of substance P, neurokinin A and an eledoisin-like component from both the spinal cord and ureter. The release of tachykinins induced by capsaicin or potassium (60 mM) was calcium dependent. No detectable release of neurokinin B or neuropeptide K, an N-terminally extended form of neurokinin A, was induced by capsaicin. No detectable release of tachykinins could be demonstrated after exposure to agents which are known to activate C-fibre afferents, such as histamine, bradykinin, serotonin, prostaglandins E1, E2 or acetylcholine. Protein extravasation in the ureter, as determined by the Evans Blue extravasation technique was used as a functional correlate to the tachykinin release. Protein extravasation was induced in vivo by local intraluminal injections of capsaicin at several hundred-fold lower concentrations than those required to induce a detectable release of tachykinins in vitro. The difference may, however, partly depend on the experimental conditions and the detection limit of the tachykinin assay used. The protein extravasation response to capsaicin was absent after systemic capsaicin pretreatment, which causes a marked depletion of tachykinins in the ureter. In conclusion, capsaicin evokes release of several tachykinins from both central and peripheral endings of primary afferent neurons. The peptides released from sensory nerves in the periphery may induce effects such as protein extravasation and smooth muscle contraction.

Animals↗
PubMed1986

Release of substance-P-like immunoreactivity in dog paw lymph after scalding injury.

The level of substance-P-like immunoreactivity (SPLI) in dog paw lymph was determined before and after scalding injury of the paw. At basal conditions, no SPLI could be detected in the paw lymph. Scalding induced an immediate increase of the SPLI-levels. Within 5-10 min after the scalding injury the levels increased up to 28 fmol ml-1 and then gradually decreased within 30-90 min after the injury. It is suggested that scalding injury results in release of substance P from sensory nerve endings, and that this release may contribute to the inflammatory response to scalding injury and, possibly, also wound healing.

Animals↗
PubMed1986

Tachykinins in carcinoid tumors: their use as a tumor marker and possible role in the carcinoid flush.

The plasma concentrations of various tachykinins were measured before and during flushing episodes in 16 patients with metastatic carcinoid tumors. The flushing attacks were induced by iv injection of pentagastrin or ingestion of food or alcohol. Tachykinins, such as neurokinin A (NKA) and neuropeptide K (NPK), increased 2-fold during flushing episodes in 12 patients, and the plasma concentrations of substance P increased to a varying extent in 3 patients. Chromatographic analysis of plasma samples taken before and during flushing episodes in 2 patients indicated the presence of individual spectra of tachykinins. In addition, the plasma concentration of tachykinin [TKLI(K12)], using an assay that detects NKA, NPK, kassinin, eledoisin, and NKB, but not substance P and physalaemin, and the urinary excretion of 5-hydroxyindole acetic acid (5-HIAA) were measured in 20 patients with midgut carcinoid tumors before and during treatment with human leucocyte interferon. The overall changes in the 2 tumor markers were concordant in 18 of the 20 patients. Thus, the Spearman correlation coefficient between the percent changes in urinary 5-hydroxyindole acid excretion and plasma TKLI(K12) was 0.54 (P less than 0.001). The patients who had a decrease in the tumor markers also had a decrease in flushing episodes and diarrhea. Plasma TKLI(K12) is a convenient tumor marker for the diagnosis and follow-up of patients with carcinoid tumors of midgut origin. The combined use of both tumor markers strengthens the diagnosis and may improve the evaluation of response during treatment.

Adult↗