Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: UNIPROT:P01189 (
beta-endorphin
)
21,003
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Increasingly strong evidence suggests that cholinergic neurons in the mesopontine tegmentum play important roles in the control of wakefulness and sleep. To understand better how the activity of these neurons is regulated, the potential afferent connections of the laterodorsal (LDT) and pedunculopontine tegmental nuclei (PPT) were investigated in the rat. This was accomplished by using retrograde and anterograde axonal transport methods and
NADPH-diaphorase
histochemistry. Immunohistochemistry was also used to identify the transmitter content of some of the retrogradely identified afferents. Following injections of the retrograde tracer wheatgerm agglutinin-conjugated horseradish peroxidase (WGA-HRP) into either the LDT or the PPT, labelled neurons were seen in a number of limbic forebrain structures. The medial prefrontal cortex and lateral habenula contained more retrogradely labelled neurons from the LDT, whereas in the bed nucleus of the stria terminalis and central nucleus of the amygdala, more cells were labelled from the PPT. Moderate numbers of neurons were seen in the magnocellular regions of the basal forebrain, and many labelled neurons were observed in the lateral hypothalamus, the zona incerta, and the midbrain central gray from both the LDT and the PPT. Accessory oculomotor nuclei in the midbrain as well as eye movement-related structures in the lower brainstem contained some neurons labelled from the LDT, and fewer neurons from the PPT. A few labelled neurons were seen in somatosensory and other sensory relay nuclei in the brainstem and the spinal cord. Retrograde labelling was seen in a number of extrapyramidal structures, including the globus pallidus, entopenduncular and subthalamic nuclei, and substantia nigra following PPT injections; with LDT injections, labelling was similar in density in the substantia nigra but virtually absent in the entopeduncular and subthalamic nuclei. Data with the fluorescent retrograde tracer fluorogold combined with immunofluorescence indicated that many neurons in the zona incerta-lateral hypothalamic region that were retrogradely labelled from the LDT contained
alpha-melanocyte-stimulating hormone
. Numerous neurons were labelled throughout the reticular formation of the brainstem following either LDT or PPT injections. Many neurons retrogradely labelled in the LDT and PPT, the dorsal and median raphe nuclei, and the locus ceruleus contained choline acetyltransferase, serotonin, and tyrosine hydroxylase, respectively. The anterograde tracers WGA-HRP and phaseolus vulgaris leucoagglutinin were used to confirm some of the projections indicated by the retrograde labelling data; anterograde labelling was seen in the LDT and PPT following injections of one of these tracers into the medial prefrontal cortex, lateral hypothalamus, and the contralateral LDT.(ABSTRACT TRUNCATED AT 400 WORDS)
...
PMID:Afferent connections of the laterodorsal and the pedunculopontine tegmental nuclei in the rat: a retro- and antero-grade transport and immunohistochemical study. 128 Nov 70
Pretreatment (i.c.v.) of mice with L-arginine but not D-arginine potentiated
beta-endorphin
-induced (i.c.v. administered) inhibition of the tail-flick response. The potentiation was attenuated by N omega-nitro-L-arginine methyl ester, a selective inhibitor of
nitric oxide synthase
. This observation suggests that increased production of nitric oxide from L-arginine mediates the potentiation of
beta-endorphin
-induced antinociception.
...
PMID:Increase of nitric oxide production by L-arginine potentiates i.c.v. administered beta-endorphin-induced antinociception in the mouse. 137 75
Previous experiments in this and other laboratories have revealed that nitric oxids (NO) plays a role in controlling the release of
corticotropin
-releasing hormone (CRH) and luteinizing-hormone-releasing hormone (LHRH). Therefore, we have investigated its role in control of growth hormone (GH) release in conscious rats by microinjecting NG-monomethyl-L-arginine (NMMA), an inhibitor of
NO synthase
(
NOS
), into the third ventricle (3V) of conscious, freely moving castrate male rats. An initial blood sample (0.3 ml) was drawn from an indwelling intra-atrial catheter just prior to injection of NMMA [1 mg in 5 microliters of 0.9% NaCl (saline)] into the 3V. To maintain the inhibitory action on
NOS
, a second injection of NMMA was administered into the 3V 60 min after the first. Additional blood samples (0.3 ml) were removed at 10 min intervals for 120 min. Other animals received injections of the diluent at the same times and volumes as NMMA. Interleukin (IL)-1 alpha (0.06 pmol in 2 microliters saline) was injected into the 3V immediately after the first injection of NMMA, whereas other animals received the NMMA diluent followed by IL-1 alpha. The effects of IL-1 alpha were almost identical to those of NMMA in that there was a dramatic lowering of plasma GH achieved primarily by a reduction in height of the GH pulses without a significant reduction in their number.(ABSTRACT TRUNCATED AT 250 WORDS)
...
PMID:Role of nitric oxide in control of growth hormone release in the rat. 748 34
The endothelins consist of a family of vasoconstrictor peptides originally isolated from endothelial tissue which are now known to be involved in neuroendocrine regulation. However, while there are data indicating the involvement of endothelins in the modulation of the hypothalamo-pituitary-adrenal (HPA) axis, the precise mechanisms involved have been unclear. We have therefore used a previously validated rat hypothalamic explant system in order to investigate the possible modulation of the neurohypophyseal hormones vasopressin and oxytocin, and
corticotropin
-releasing hormone (CRH), by endothelin-1 (ET-1) and endothelin-3 (ET-3). Following a period of stabilisation, the release of vasopressin, oxytocin and CRH remained approximately constant in successive 20-min incubations. Addition of ET-1 stimulated the release of vasopressin at a dose of 0.1 nmol/l (p < 0.05), and both vasopressin and oxytocin at 10 nmol/l (p < 0.01 and 0.05, respectively). The release of vasopressin and oxytocin induced by 10 nmol/l ET-1 were both totally blocked by co-incubation with either 1 or 10 mumol/l of the specific ETA receptor subtype antagonist cyclo (D-Trp-D-Asp-Pro-D-Val-Leu) (BQ-123). ET-1 had no effect on CRH release in the dose range of 0.1-1,000 nmol/l. In case any possible stimulation of CRH might be masked by simultaneous generation of nitric oxide (NO), an inhibitor of CRH secretion, addition of ET-1 was also carried out in the presence of the
NO synthase
inhibitor, L-NO-Arg: ET-1 was again without effect in this dose range.(ABSTRACT TRUNCATED AT 250 WORDS)
...
PMID:Endothelin-1 stimulates the in vitro release of neurohypophyseal hormones, but not corticotropin-releasing hormone, via ETA receptors. 753 87
The aim of this study was to investigate the neurochemical coding of myenteric neurons in the guinea pig gastric corpus by using immunohistochemical methods. Antibodies and antisera against calbindin (CALB), calretinin (CALRET), choline acetyltransferase (ChAT), calcitonin gene-related peptide (CGRP), dopamine beta-hydroxylase (DBH),
beta-endorphin
(ENK), neuropeptide Y (NPY), neuron-specific enolase (NSE),
nitric oxide synthase
(
NOS
), protein gene product 9.5 (PGP), parvalbumin (PARV), serotonin (5-HT), somatostatin (SOM), substance P (SP), tyrosine hydroxylase (TH), and vasoactive intestinal peptide (VIP) were used. Double- and triple-labeling studies revealed colocalization of certain transmitters and enabled the identification of distinct subpopulations of gastric enteric neurons. NPY/VIP/
NOS
/ENK were present in 28% of all neurons, whereas 11% had NPY/VIP/DBH/ChAT;
NOS
-only neurons made up 2% of the population. The combination SP/ChAT/ENK occurred in 21% of the population, whereas SP/ChAT/ENK/CALRET and SP/CHAT/SOM/ +/- CALRET was identified in 5% and 6% of all cells, respectively. 5-HT-containing neurons comprised 2% of all cells and could be further classified by the presence of additional antigens as 5-HT/SP/(ChAT) or 5-HT/VIP/(ChAT). Approximately 21% of all neurons contained only ChAT with no additional antigen present and are referred to as ChAT/-. Gastric myenteric ganglion cells were not immunoreactive for CALB, PARV, CGRP, or TH. The results of this study indicate that gastric myenteric neurons can be characterized on the basis of different chemical coding. Neurochemical coding of corpus myenteric neurons revealed some similarities and significant differences in comparison with other regions of the gut. These differences might reflect adaptation of enteric nerves according to regional specialization and the distinct functions of the proximal stomach as a gastric reservoir.
...
PMID:Neurochemical coding of enteric neurons in the guinea pig stomach. 753 52
On the basis of the comparing of the distribution of
beta-endorphin
-like immunoreactive neuronal fibres and
nitric oxide synthase
-like immunoreactive neurons in the dorsal raphe nucleus, the synapses between the two immunocytochemically identified neurons were studied with a modified DAB-silver-gold intensification double immunostaining technique at the electron microscopic level. Although both of them can be found in the mediodorsal and medioventral parts of the dorsal raphe nucleus, the synapses between them could only be found in the mediodorsal part. The majority of the
beta-endorphin
-like immunoreactive neuronal fibers contained many dense-cored vesicles. The synapses made by
beta-endorphin
-like immunoreactive neuronal axon terminals on
nitric oxide synthase
-like immunoreactive neurons were both symmetrical and asymmetrical with the former predominant, especially in the axo-dendritic ones. beta-Endorphin-like immunoreactive perikarya could only be found in the ventrobasal hypothalamus. These findings suggest the possibility that the
beta-endorphin
- producing neurons in the ventrobasal hypothalamus could influence
nitric oxide synthase
-containing neurons in the dorsal raphe nucleus by synaptic relations.
...
PMID:Immunoelectron microscopy of beta-endorphinergic synaptic innervation of nitric oxide synthase immunoreactive neurons in the dorsal raphe nucleus. 758 21
Previous work has suggested that the antinociceptive effect of nitrous oxide (N2O) in rats is mediated, at least in part, by
beta-endorphin
(beta-EP) and that centrally administered beta-EP stimulates release of methionine-enkephalin (ME) in the rat spinal cord. Since inhibition of central nitric oxide (NO) production has been found to suppress N2O antinociception, we examined the possible involvement of NO in the release of spinal cord ME by i.c.v. beta-EP. Urethane-anesthetized, male Sprague-Dawley rats were intrathecally (i.t.) perfused with artificial cerebrospinal fluid (aCSF) and fractions of perfusate were assayed for immunoreactive (i.r.) ME. The beta-EP-induced increase in ME concentration in the i.t. perfusate was significantly suppressed by perfusing the animal with aCSF containing 100 microM L-NG-nitro arginine (L-NOARG), an inhibitor of
NO synthase
(
NOS
). The further addition of 50 microM L-arginine (L-ARG), but not D-arginine (D-ARG), to the aCSF reversed the suppression of the ME change by L-NOARG. However, the potency of L-ARG decreased with increasing concentrations of L-ARG. On the other hand, increasing the concentration of L-NOARG in the aCSF to 250 microM failed to produce a greater suppression of the beta-EP-induced increase in ME. These findings suggest that NO may mediate the beta-EP-induced release of ME in the spinal cord and that interference with this mechanism might be an explanation for the antagonism of N2O antinociception in rats by
NOS
inhibitors.
...
PMID:Involvement of nitric oxide in intracerebroventricular beta-endorphin-induced neuronal release of methionine-enkephalin. 779 28
Superfusion of rat hypothalamic slices with 10(-4) M N-methyl-D-aspartic acid (NMDA) resulted in increased release of
alpha-melanocyte-stimulating hormone
(
alpha-MSH
). Peptide release was blocked by 10(-6) M NG-nitro-L-arginine methyl ester (L-NAME) a specific competitive inhibitor of
nitric oxide synthase
but not by the inactive enantiomer D-NAME at 10(-6) M. The inhibition by L-NAME was reversed by the addition of 10(-5) mM L-arginine, an excess of enzyme substrate. Release of nitric oxide products into tissue superfusates was stimulated by a 50 mM concentration of potassium ions and by 10(-4) M NMDA. Potassium-stimulated release was blocked by L-NAME. Basal, potassium-stimulated and NMDA-stimulated release of nitric oxide products were significantly inhibited by the NMDA-receptor antagonist D(-)-2-amino-5-phosphopentanoic acid (AP5) at 10(-4) M and by the NMDA-channel blocker ketamine at 10(-4) M. We conclude that nitric oxide mediates the stimulatory action of glutamic acid on the release of
alpha-MSH
from the rat hypothalamus.
...
PMID:N-methyl-D-aspartate (NMDA) stimulates release of alpha-MSH from the rat hypothalamus through release of nitric oxide. 788 30
Although cocaine shares the ability of fenfluramine to inhibit the synaptic reuptake of serotonin, previous observations from our group suggest that the genomic effects of fenfluramine in the rat striatum are primarily mediated by dopaminergic rather than serotonergic mechanisms. To compare and further understand the nerve cell type(s) targeted by psychotropic drugs, we studied, by use of immunocytochemistry and in situ hybridization, changes in c-fos in brain nerve cells of the caudate putamen and hypothalamus following acute cocaine or fenfluramine exposure. Predictably, both drugs (20 mg/kg; i.p.) evoked rapid but transient increases in c-fos in the caudate putamen. In addition, double labeling immunocytochemistry indicated that Fos-like protein was expressed preferentially in striatal neurons containing the protein phosphatase inhibitor, DARPP-32. In contrast, fenfluramine, but not cocaine, elicited c-fos mRNA and Fos-like protein in the neuroendocrine paraventricular nucleus (PVN) of the hypothalamus despite the fact that both drugs are known to be equally capable to stimulate the hypothalamic-pituitary-adrenal (HPA) axis. This difference is discussed in terms of serotonergic, dopaminergic and DARPP-32 input to hypothalamic neurons and tanycytes associated with
adrenocorticotropin
hormone (ACTH) secretion. To further identify the phenotypes of nerve cells expressing c-fos by fenfluramine in the PVN, it was demonstrated that the immediate-early gene was induced in a subpopulation of neurons constitutively expressing
nitric oxide synthase
(
NOS
). Taken together, we identified a number of common and disparate actions of cocaine and fenfluramine in striatal and hypothalamic tissue, thereby suggesting that c-fos induction in these two brain structures is differentially regulated by intrinsic events in addition to neuronal phenotype. We propose that the genomic effects produced by these two drugs represent part of a general dopaminergic and glutamateric mechanism by which monoamine reuptake inhibitor drugs affect specific brain nerve cells.
...
PMID:Induction of c-fos in rat brain by acute cocaine and fenfluramine exposure: a comparison study. 806 90
We have investigated the regulatory role of nitric oxide (NO) in
corticotropin
-releasing hormone (CRH) release from the human perfused placental lobule in vitro. The effects of the NO donor sodium nitroprusside, the
NO synthase
inhibitor N omega-nitro-L-arginine, and the NO substrate L-arginine on human (h) placental CRH secretion have been studied. Single lobules of term placentae were bilaterally perfused with Krebs solution (5 mL/min; 95% O2-5% CO2; 37 C; pH 7.3). Fetal and maternal perfusates were collected at 4 C every 30 min for 3 h. CRH immunoreactivity (CRH-IR) in perfusates was measured by RIA using the 41-residue synthetic CRH as standard, 125I-labeled Tyr-hCRH as tracer, and a rabbit anti-CRH antibody Y2BO. The sensitivity of the assay was 0.13 pmol/L. Under basal conditions, human perfused placentae in vitro continuously secreted CRH-IR, which diluted in parallel to a synthetic hCRH-(1-41) standard curve. Size-exclusion chromatography of placental perfusates using a Sephadex G-50 column indicated that placental CRH-IR predominately coeluted with hCRH-(1-41) standard. Basal maternal perfusate CRH-IR levels (27 +/- 4 pmol/L) released from perfused placental lobules were nearly 10-fold greater than fetal perfusate CRH-IR levels (3.4 +/- 0.7 pmol/L; P < 0.05). Infusion of sodium nitroprusside (30-100 mumol/L) into the maternal and fetal placental circulations inhibited CRH-IR release into maternal perfusate in a concentration-dependent manner, but did not inhibit CRH-IR release into the fetal perfusate. N omega-nitro-L-arginine (100 mumol/L) increased placental CRH-IR secretion into fetal perfusate, and this effect was reversed by the infusion of L-arginine (100 mumol/L), which also reduced release below basal levels. In contrast, maternal perfusate CRH-IR levels were not affected by N omega-nitro-L-arginine or L-arginine. These results indicate that the human perfused placenta in vitro releases a substance of similar mol wt and hCRH-IR. Moreover, modulators of the NO signaling pathway differentially affect placental secretion of CRH-IR into the maternal and fetal perfusates. These data are consistent with the involvement of NO in the regulation of placental CRH release during pregnancy.
...
PMID:Nitric oxide regulation of corticotropin-releasing hormone release from the human perfused placenta in vitro. 863 1
1
2
3
4
5
6
7
8
Next >>