Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:P61278 (somatostatin)
 22,083 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The effect and mode of action of vasoactive intestinal polypeptide (VIP), a peptidergic neuromodulator in the gastrointestinal nervous system, were investigated in isolated muscle strips of the guinea-pig ileum. VIP induced concentration-dependent (20 nM-1 microM) contractions of longitudinal ileal strips. TTX (1 microM), a mixture of atropine (3 microM) and spantide (30 microM), a mixture of atropine (3 microM) and omega-conotoxin GVIA (100 nM), somatostatin (60 nM) and dynorphin (100 nM) abolished the effect of VIP. In most cases a small relaxation became evident. Desensitization to substance P in the presence of atropine prevented VIP-induced contraction. A partial inhibition was observed in the presence of atropine (3 microM), spantide (30 microM), omega-conotoxin GVIA (100 nM), beta-endorphin (265 nM), met-enkephalin (1100 nM) and a mixture of spantide (30 microM) and omega-conotoxin GVIA (100 nM). The action of VIP was not significantly modified by guanethidine (3 microM) or hexamethonium (150 microM). In circular ileal strips VIP (10-300 nM) caused concentration-dependent relaxations through a direct myogenic effect. These results indicate that the VIP produced contractions of the guinea-pig ileum are exclusively neurally mediated and involve a cholinergic as well as a noncholinergic-nonadrenergic (NANC) pathway. It is concluded that besides acetylcholine (Ach) VIP releases the peptidergic transmitter substance P from postganglionic nerve fibers of myenteric plexus. Opioid peptides and somatostatin modulate the activity of cholinergic and peptidegic nerves in the guinea-pig ileum. The release of substance P appears to depend completely on N-type voltage sensitive calcium channels.
 ...
PMID:Vasoactive intestinal polypeptide induces neurogenic contraction of guinea-pig ileum. Involvement of acetylcholine and substance P. 137 93

The general morphology of the intramural innervation of the myenteric plexus of the axolotl stomach has been investigated using antisera raised against neuron-specific enolase and a microtubule-associated protein. Additionally, the occurrence of serotonin and several peptidergic neurotransmitter/neuromodulator substances was studied. Immunoreactivity for galanin, vasoactive intestinal polypeptide, substance P and neuromedin U was found in both fibres and intrinsic perikarya, whereas the serotonin and calcitonin gene-related peptide-like-substance-containing nerve fibres seemed to be of extrinsic origin. The axolotl stomach myenteric plexus appeared to be devoid of enkephalin-, neuropeptide Y-, somatostatin- and bombesin-like immunoreactive nerve fibres and nerve cell bodies. Double labelling experiments revealed the presence of a subpopulation of substance P/calcitonin gene-related peptide-like immunoreactive nerve fibres. Contrary to mammals, no coexistence of neuromedin U and substance P was found. Our findings illustrate that besides a number of similarities, considerable species differences exist between urodeles and anurans with regard to the organization of the enteric nervous system.
 ...
PMID:Morphological features of the myenteric plexus of the stomach of the axolotl, Ambystoma mexicanum, revealed by immunocytochemistry. 137 7

Glutaminase has been considered to be a synthesizing enzyme of transmitter glutamate in pyramidal neurons of the cerebral cortex. In the present study, an attempt was made to examine with a double immunofluorescence method whether or not nonpyramidal neurons of the cerebral cortex are immunoreactive for glutaminase. Glutaminase was stained with mouse anti-glutaminase IgM and FITC-labeled anti-[mouse IgM] antibody. In the same section, parvalbumin (PA), calbindin (CB), choline acetyltransferase (CAT), vasoactive intestinal polypeptide (VIP), corticotropin releasing factor (CRF), cholecystokinin (CCK), somatostatin (SS), or neuropeptide Y (NPY) was visualized as a marker for nonpyramidal neurons with an antibody to each substance, biotinylated secondary antibody and Texas Red-labeled avidin. Virtually no glutaminase immunoreactivity was seen in PA-, CB-, CAT-, VIP-, CRF-, CCK-, SS-, or NPY-immunoreactive neuronal perikarya in the neocortex and mesocortex (cingulate and retrosplenial cortices), although it was detected in a few PA-, CB-, VIP-, CCK-, SS-, or NPY-immunoreactive nonpyramidal neurons in the piriform, entorhinal, and hippocampal cortices. PA- and CB-positive neurons have been reported to constitute the major population of GABAergic neurons in the cerebral cortex. Thus, the present results, together with the previous reports, suggest that most GABAergic, cholinergic and peptidergic nonpyramidal neurons in the neo- and mesocortex do not contain glutaminase.
 ...
PMID:Paucity of glutaminase-immunoreactive nonpyramidal neurons in the rat cerebral cortex. 138 31

Single- and dual-labelling immunohistochemistry were used to determine the distribution and coexistence of neuropeptides in perivascular nerves of the large arteries and veins of the snake, Elaphe obsoleta, using antibodies for vasoactive intestinal polypeptide, substance P, calcitonin gene-related peptide, neuropeptide Y, galanin, somatostatin, and leu-enkephalin. Blood vessels were sampled from four regions along the body of the snake: region 1, arteries and veins anterior to the heart; region 2, central vasculature 5 cm anterior and 10 cm posterior to the heart; region 3, arteries and veins in a 30-cm region posterior to the liver; and region 4, dorsal aorta and renal arteries, renal and intestinal veins, 5-30 cm cephalad of the vent. A moderate to dense distribution of vasoactive intestinal polypeptide-like immunoreactive fibres was found in most arteries and veins of regions 1-3, but fibres were absent from the vessels of region 4. The majority of vasoactive intestinal polypeptide-like immunoreactive fibres contained colocalized substance P-like immunoreactivity, and these fibres were unaffected by either capsaicin or 6-hydroxydopamine (6-OHDA) pretreatment. In the anterior section of the snake, the vagal trunks contained many cell bodies with colocalized vasoactive intestinal polypeptide and substance P-like immunoreactivity. It is suggested that the vasoactive intestinal polypeptide/substance P-like immunoreactive cell bodies and fibres are parasympathetic postganglionic nerves. Neuropeptide Y-like immunoreactive fibres were observed in all arteries and veins, being most dense in regions 3 and 4. The majority of these fibres also contained colocalized galanin-like immunoreactivity, and were absent in tissues from 6-OHDA pretreated snakes, suggesting that neuropeptide Y and galanin are colocalized in adrenergic nerves. A small number of neuropeptide Y-like immunoreactive fibres contained vasoactive intestinal polypeptide but not galanin, and were unaffected by 6-OHDA treatment. All calcitonin gene-related peptide-like immunoreactive fibres contained colocalized substance P-like immunoreactivity, and these fibres were observed in all vessels, being particularly dense in the carotid artery and jugular veins. All calcitonin gene-related peptide/substance P-like immunoreactive fibres appeared damaged after capsaicin treatment suggesting they represent fibres from afferent sensory neurons. A sparse plexus of somatostatin-like immunoreactive fibres was observed in the vessels only from region 4. No enkephalin-like immunoreactive fibres were found in any blood vessels from any region. This study provides morphological evidence to suggest that there is considerable functional specialization within the components of the rat snake peripheral autonomic system controlling the circulation, in particular the regulation of venous capacitance.
 ...
PMID:The distribution and colocalization of neuropeptides in perivascular nerves innervating the large arteries and veins of the snake, Elaphe obsoleta. 138 80

This is the first investigation of alterations in the innervation of the obstructed human bladder by nerves containing neuropeptides. The patient groups studied were those with stable detrusor function, those with unstable detrusor function, and those presenting with acute retention of urine. Specimens of bladder tissue were taken from the lateral wall of the bladder below the peritoneal reflection. A total of 23 patients was studied (control, n = 4; acute retention, n = 5; stable obstruction, n = 5; unstable obstruction, n = 9). Substance P, calcitonin gene-related peptide and vasoactive intestinal polypeptide levels in the bladder were quantified by immunoassay. The density of innervation of the bladder detrusor by nerves containing these neurotransmitters and by those containing neuropeptide Y and somatostatin was assessed using both semiquantitative and quantitative immunohistochemical techniques. A reduction in the density of innervation by vasoactive intestinal polypeptide, calcitonin gene-related peptide, substance P and somatostatin-immunoreactive but not neuropeptide Y-immunoreactive nerve fibres was shown in the obstructed bladder. These findings, combined with the significant reduction in substance P content of the obstructed bladder and in particular of the acute retention bladder, indicate that there may be an afferent nerve dysfunction resulting from prostatic bladder outflow obstruction.
 ...
PMID:Loss of sensory neuropeptides in the obstructed human bladder. 145 Aug 44

Vibratome sectioning of paraformaldehyde-fixed brains containing a lesion and/or intracerebroventricular grafts and staining of these sections often lead to damage around the site of the lesion and loss of the implants. Various embedding procedures were compared in order to find a method to overcome this problem. The best results were obtained when fixed brain tissue was first embedded under reduced pressure in 10% gelatin at 50 degrees C, and then fixed again, in 4% paraformaldehyde. The method did not affect the immunocytochemical staining for vasopressin, vasoactive intestinal polypeptide, somatostatin, gonadotropin releasing hormone and neuropeptide Y.
 ...
PMID:Gelatin embedding to preserve lesion-damaged hypothalami and intracerebroventricular grafts for vibratome slicing and immunocytochemistry. 152 72

The presence of immunoreactivity to the neuronal phosphoprotein B-50 and the peptides bombesin, calcitonin gene-related peptide, galanin, neurotensin, neuropeptide Y, somatostatin, substance P, and vasoactive intestinal polypeptide was examined in biopsy specimens from the duodenum and rectum of human immunodeficiency virus (HIV)-seropositive and HIV-seronegative male homosexual patients. The distribution of B-50 and the peptides was correlated with HIV serology, number of CD4+ lymphocytes, and the presence of HIV in biopsy culture. There was a very low incidence of enteric pathogens in both groups of patients. It was found that HIV-seropositive patients had a greater incidence of abnormal patterns of immunoreactivity (reduced intensity and/or density of innervation) in enteric nerves and enteroendocrine cells than HIV-seronegative patients. A reduction of substance P immunoreactivity was significantly correlated with reduced CD4+ lymphocyte count and HIV status; a similar trend was also seen for somatostatin and vasoactive intestinal polypeptide. Using B-50 as a marker, it was found that both groups of patients had altered patterns of immunoreactivity in rectal nerves. The findings of this study suggest that some of the clinical symptoms associated with HIV infection may be caused by a specific HIV enteropathy that influences enteric nerve and/or enteroendocrine cell function by altering the density of peptide immunoreactivity.
 ...
PMID:Peptides in the gastrointestinal tract in human immunodeficiency virus infection. The GI/HIV Study Group of the University of Calgary. 153 25

Basic fibroblast growth factor (bFGF) has been thought to act as a neurotrophic factor during early developmental stages in various brain regions, including the hypothalamus. In the present paper, we have studied the effect of bFGF on peptide-containing neurons cultured from the postnatal (1-3 days and 14 days after birth) rat hypothalamus. The addition of bFGF, or acid FGF (aFGF), to serum-free culture medium increased both survival and neurite growth of growth hormone-releasing factor (GRF)-containing neurons. The potency of bFGF was more than 10 times as great as that of aFGF. Insulin-like growth factor I (IGF-I) did not have any significant effect on the survival of GRF neurons. Further, neither IGF-I nor aFGF modified the survival-promoting effect of bFGF on GRF neurons. bFGF promoted the survival of somatostatin- and vasoactive intestinal polypeptide-containing neurons, too.
 ...
PMID:Neurotrophic effects of fibroblast growth factors on peptide-containing neurons in culture from postnatal rat hypothalamus. 162 Feb 87

Calcitonin gene-related peptide is a putative neurotransmitter of central and peripheral nervous systems which coexists with acetylcholine in motor nerve terminals and exerts multiple effects on skeletal muscle, suggesting a trophic role for this neuropeptide. Using radiolabeled calcitonin gene-related peptide as a probe in a specific binding assay, we have characterized calcitonin gene-related peptide binding sites on chick skeletal muscle membranes. Binding is time-dependent, saturable and reversible. Scatchard analyses revealed two classes of sites: high-affinity sites with a KD value of 62 pM, and low-affinity sites with a KD value of 3.3 nM. The maximal number of sites is, respectively, 22 and 155 fmol/mg protein for high- and low-affinity binding sites. Specific binding was not affected by the presence, in excess, of other neuropeptides such as salmon calcitonin or somatostatin or vasoactive intestinal polypeptide. Affinity of the binding site for calcitonin gene-related peptide was decreased in the presence of 5'-guanylyl-imidodiphosphate, suggesting a physiological coupling of calcitonin gene-related peptide receptor to a GTP binding protein. In a developmental study of chick muscle, we found the highest activity of calcitonin gene-related peptide binding sites in 11-14 day embryos, following a pattern of evolution similar to that of acetylcholine receptors (constant ratio of 12 acetylcholine receptors per calcitonin gene-related peptide binding site). However, both receptors appear differentially regulated: while the number of acetylcholine receptors increases 5-16-fold after denervation, calcitonin gene-related peptide binding sites slightly diminish in number. These results are discussed in terms of the physiological significance of calcitonin gene-related peptide binding sites on chick skeletal muscle membrane.
 ...
PMID:Characterization and developmental evolution of a high-affinity binding site for calcitonin gene-related peptide on chick skeletal muscle membrane. 165 62

Glutamate and several neuropeptides are synthesized and released by subpopulations of primary afferent neurons. These sensory neurons play a role in regulating the inflammatory and immune responses in peripheral tissues. We have explored what changes occur in the location and concentration of receptor binding sites for sensory neurotransmitters in two human inflammatory diseases, ulcerative colitis and Crohn's disease, using quantitative receptor autoradiography. The sensory neurotransmitter receptors included bombesin, calcitonin gene-related peptide-alpha, cholecystokinin, galanin, glutamate, somatostatin, neurokinin A (substance K), substance P, and vasoactive intestinal polypeptide. Of the nine receptor binding sites examined only binding sites for substance P and vasoactive intestinal peptide were significantly altered in the inflamed tissue. These data suggest that substance P is involved in regulating the inflammatory and immune responses in human inflammatory diseases and indicate a specificity of efferent action for each sensory neurotransmitter in peripheral tissues.
 ...
PMID:Alterations in receptors for sensory neuropeptides in human inflammatory bowel disease. 165 49


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>