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

Somatostatin-immunoreactive neurons in the rat neostriatum were studied by correlated light and electron microscopy using the peroxidase-antiperoxidase immunocytochemical technique. Immunoreactivity was localized in neuronal perikarya and processes. The perikarya were of spindle or fusiform shape (average length 16.9 microns) and were found in all parts of the neostriatum. From each neuron there arose two to four straight immunoreactive dendritelike processes, which could frequently be traced as far as about 130 microns from their perikaryon. Immunoreactive varicose axonlike processes were occasionally found, some of which were proximal axons of identified immunoreactive cells. Nine of the light microscopically identified neurons showing somatostatin-immunoreactivity were studied in the electron microscope; two of them had proximal axons with varicosities. Each neuron had an oval or elongated nucleus, which was always indented. These morphological features correspond well to those of certain "medium-size aspiny" neurons classified by Golgi studies. Although the immunoreactive endproduct was diffusely located throughout the neuron, it was characteristically located in the saccules and large granules (diameter 133 nm) of the Golgi apparatus, and large immunoreactive vesicles of similar size to those in the Golgi apparatus frequently occurred in all parts of axon. Very little synaptic input was found on the perikarya and dendrites of somatostatin-immunoreactive neurons. The perikarya and proximal dendrites received both symmetrical and asymmetrical synaptic input, while the distal dendrites usually received boutons that formed asymmetrical contacts. The somatostatin-immunoreactive boutons contained pleomorphic electron-lucent vesicles (diameter 39.3 nm) and a few large immunoreactive granular vesicles; these boutons always formed symmetrical synapses. Their postsynaptic targets were dendritic shafts, spines, and unclassified dendritic profiles. On the other hand, the varicosities of identified proximal axons of somatostatin-positive neurons did not form typical synapses, since they lacked clusters of small vesicles, but some of them were in direct apposition (via membrane specializations) to unlabelled perikarya or dendrites. It is concluded that somatostatin is a useful marker for a particular type of neuron in the neostriatum. The presence of somatostatin immunoreactivity in synaptic boutons is consistent with the view that somatostatin could be a neurotransmitter in the neostriatum.
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PMID:Fine structural studies on a type of somatostatin-immunoreactive neuron and its synaptic connections in the rat neostriatum: a correlated light and electron microscopic study. 613 37

As medical treatment of haemorrhage from esophageal varices vasopressin is discussed. The analogue triglycyl-vasopressin has less side-effects and a longer plasma half-life. According to the first randomized study with only a small number of patients bleeding from varices triglycyl-vasopressin was superior to vasopressin. The efficacy of somatostatin to reduce splanchnic blood flow in patients with liver cirrhosis is controversial. In a placebo-controlled trial propranolol prevented rebleeding from varices in patients with cirrhosis. However, beta-blockers should not be given to patients with advanced cirrhosis. Several controlled studies prove cimetidine not to be effective in ulcer bleeding. Somatostatin and secretin could be candidates for pharmacotherapy of haemorrhage from ulcers and erosions. In an own randomized and multicenter trial on 100 patients with stopped ulcer bleeding it was proven that the combination of the synergistically acting receptor antagonists cimetidine and pirenzepine prevent rebleeding significantly better than a prophylactic treatment of either cimetidine or pirenzepine alone. An improvement of mortality rates of upper gastrointestinal bleeding seems also to be possible by using such a combined prophylaxis. As prophylaxis of stress-ulcer bleeding cimetidine - recently ranitidine, too - and antacids are applied. Instead of a widely used enhancement of the doses of H2-blockers a combined application of H2-receptor antagonists and pirenzepine is also recommended in this indication which offers theoretical and practical advantages.
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PMID:[Drug therapy and prevention of acute upper gastrointestinal hemorrhage]. 613 16

Somatostatin 28(1-14) immunoreactivity is present in dorsal root ganglion cells and in the superficial laminae of the spinal cord in the rat. The distribution of somatostatin 28(1-14) immunoreactive varicosities in the dorsal horn corresponds well to the distribution of somatostatin 14 immunoreactive elements. Some dorsal root ganglion cells exhibit both somatostatin 14 and somatostatin 28(1-14) immunoreactivities.
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PMID:Somatostatin 28(1-14) immunoreactivity in primary afferent neurons of the rat spinal cord. 614 18

The distribution of vasopressin-, vasoactive intestinal polypeptide-, somatostatin-, avian pancreatic polypeptide-, 5-hydroxytryptamine- and glutamic acid decarboxylase-like immunoreactivity was analyzed in the suprachiasmatic nuclei of male and female golden hamsters. Vasopressin. Vasopressin-like immunoreactivity is localized within neurons, dendrites and axons throughout the rostrocaudal extent of the suprachiasmatic nuclei. Immunoreactive perikarya are restricted to the dorsomedial aspect of each nucleus and occur in highest numbers within the intermediate two-thirds of the rostrocaudal axis. Axons containing vasopressin-like immunoreactivity form a dense plexus in the dorsomedial suprachiasmatic nuclei and in a vertical column at the lateral aspect of each nucleus. Somatostatin. Somatostatin-like immunoreactivity is also contained in neurons in the dorsomedial aspect of the suprachiasmatic nuclei and in thin varicose axons distributed throughout the suprachiasmatic nuclei in a pattern similar to that of vasopressin-immunoreactive axons. Vasoactive intestinal polypeptide. Vasoactive intestinal polypeptide-immunoreactive neurons are concentrated in the ventrolateral portion of each nucleus and occur almost exclusively within the intermediate two-thirds of the rostrocaudal axis. An extremely dense plexus of varicose axons exhibiting vasoactive intestinal polypeptide-like immunoreactivity extends throughout the suprachiasmatic nuclei and passes out of the dorsal aspect of each nucleus into the periventricular and anterior hypothalamic areas. Avian pancreatic polypeptide. Avian pancreatic polypeptide-like immunoreactivity is restricted to axons which arborize within the ventrolateral aspect of each nucleus. These fibers extend throughout the rostrocaudal extent of each nucleus and partially overlap the terminal field of retinal afferents. Glutamic acid decarboxylase. A very dense plexus of axonal varicosities exhibiting glutamic acid decarboxylase-like immunoreactivity fills both the dorsomedial and ventrolateral portions of the suprachiasmatic nuclei throughout the rostrocaudal extent of each nucleus. Lightly stained immunoreactive perikarya also occur throughout the suprachiasmatic nuclei. 5-Hydroxytryptamine. 5-Hydroxytryptamine-like immunoreactivity is restricted to axons which form a plexus in the ventromedial portion of each nucleus that is most dense in the intermediate two-thirds of the rostrocaudal axis.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:The suprachiasmatic nucleus of the golden hamster: immunohistochemical analysis of cell and fiber distribution. 615 Nov 47

The occurrence and distribution of substance P (SP), somatostatin (SOM), and enkephalin (ENK) immunoreactive elements were examined in the spinal cord of the domestic fowl, Gallus domesticus. SP immunoreactive fibers and their varicosities were densest in laminae I and II, although they were also found within deeper regions of the dorsal horn. In contrast, the intermediate gray area, the area around the central canal, and the ventral horn, contained fewer SP immunoreactive fibers. The distribution of ENK immunoreactivity in the gray matter was similar to that described for SP although immunoreactive fibers were denser around the central canal and in the intermediate zone. Few SOM immunoreactive fibers were present in the dorsal horn, the area around the central canal, and the ventral horn. All three peptidergic immunoreactive elements were found in and around the nucleus of Terni, an autonomic area. Throughout the lumbosacral enlargement SP, SOM, and ENK immunoreactive varicosities were found adjacent to the lumbosacral sinus and in fibers traversing the glycogen body. In addition, at caudal lumbar and rostral sacral levels a plexus of SP and SOM immunoreactive fibers was observed to be in close relationship with presumed motoneurons.
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PMID:Substance P, somatostatin, and methionine enkephalin immunoreactive elements in the spinal cord of the domestic fowl, Gallus domesticus. 618 82

The distribution of substance P (SP)- and somatostatin (SOM)-immunoreactive elements in the spinal cord of the neonatal rat was examined. With few exceptions, the distribution of SP-immunoreactive elements is similar to that described for the adult. A major difference is the obvious presence of SP-immunoreactive fibers in all funiculi of neonatal cords. In addition, an obvious small bundle of longitudinal SP immunoreactive fibers is seen in the base of the dorsal horn at rostral cervical levels. Unlike that of the adult, the neonatal spinal cord shows a widespread distribution of SOM-immunoreactivity. SOM-immunoreactive fibers are present in all funiculi. SOM-immunoreactive perikarya of various shapes and sizes are widely dispersed throughout the gray matter. The cell density is increased in the superficial laminae of the dorsal horn, in a region ventral-lateral to the central canal and in the ventral horn. SOM-immunoreactive varicosities are present in moderate amounts in the superficial laminae of the dorsal horn but are extremely sparse in other regions of the gray matter. A few SOM-immunoreactive fibers course longitudinally at the base of the dorsal horn at rostral levels of the cord. These fibers are found in the same region occupied by the longitudinal SP-immunoreactive fibers referred to above.
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PMID:Widespread distribution of substance P- and somatostatin-immunoreactive elements in the spinal cord of the neonatal rat. 619 26

We have used antisera specifically directed against Met-enkephalin (met-ENK), somatostatin (SOM), substance P (SP), and vasoactive intestinal peptide (VIP), to study the development of neurons containing these peptides in the foregut of the chick. All four peptides were detected early in ontogeny, at 4 to 9 days of incubation (d.i.), and were localized primarily to cell bodies in the primitive myenteric plexus. There were differences in the times at which they were first detected and in the sequence of their appearance in the proventriculus, gizzard, and duodenum. The differentiation of these peptidergic neurons in the duodenum was examined in some detail. Cell bodies containing these peptides were first detected in the primitive myenteric plexus at 5 to 7 d.i. and increased in number from 7 to 11 d.i. Processes containing varicosities became prominent between 11 and 13 d.i. VIP was the first of the peptides to appear in the submucosal plexus and was found in more proximal regions of the duodenum at 5 d.i. Shortly thereafter, SOM- and SP-containing cell bodies were seen; met-ENK-containing cell bodies were never detected in the submucosal plexus. At 13 d.i., the circular smooth muscle contained a number of VIP-immunoreactive and a smaller number of SOM-immunoreactive processes. met-ENK- and SP-immunoreactive processes appeared in the circular smooth muscle between 17 and 21 d.i.; VIP- and SP-immunoreactive processes appeared in the mucosal plexus at 17 to 21 d.i. Our results suggest that neuropeptides appear very early in the ontogeny of enteric neurons, at the same time or even before cholinergic and serotonergic neurons express their phenotypes. These findings argue against a sequential developmental order in which peptidergic neurons appear after those containing acetylcholine and serotonin.
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PMID:The development of peptidergic neurons in the foregut of the chick. 619 17

The localization of substance P-(SP-), methionine-enkephalin (met-Enk-) and somatostatin (SOM-)like immunoreactivity was studied in the cat pyloric sphincter, ileum, ileocecal sphincter and proximal colon. The enteric plexuses in all regions examined contained SP-, met-Enk- and SOM-like immunoreactive varicose nerve fibres. A large number of especially SP- and met-Enk-containing varicosities were often seen to encircle the nerve cell bodies and processes in the two ganglionic plexuses. The SOM-like immunoreactive perikarya were the only peptide-containing nerve cells, preferentially located in the submucous ganglia. The predominant localization of the SOM-like immunoreactive neurons in the two enteric plexuses of the ileum was the most pronounced regional difference in the distribution pattern of the peptides. Among the layers of the cat intestinal wall the circular muscle contained the most peptide-immunoreactive fibres in contrast to the longitudinal muscle. Evidence was obtained for the occurrence of single peptide-immunoreactive varicose nerve fibres in muscularis mucosae as well as around the glands and the blood vessels. Immunoreactive endocrine cells occurred mainly in the ileum mucosa.
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PMID:Immunocytochemical localization of substance P, methionine-enkephalin and somatostatin in the cat intestinal wall. 620 22

An immunohistochemical and immunoelectron microscopic study was used to demonstrate tyrosine hydroxylase (TH) and dopamine beta-hydroxylase (DBH) immunoreactivities in the rat pancreas. Small TH immunoreactive cells were found in close contact with large TH immunonegative ganglion cells among the exocrine glands and were occasionally found in some islets. Some of these TH immunoreactive cells were also DBH immunopositive. The immunoreaction product was seen diffusely in the cytoplasm and in the granule cores of TH immunoreactive cells. All intra-pancreatic ganglion cells were immunoreactive for DBH, but not for TH. The TH immunoreactive cells were identified as small intensely fluorescent (SIF) cells due to their localization and morphological characteristics and showed no insulin, glucagon, somatostatin or pancreatic polypeptide immunoreactivities. These results indicate that SIF cells may release dopamine or noradrenaline to adequate stimuli while the intra-pancreatic ganglion cells with only DBH may not synthesize catecholamines in a normal biosynthetic pathway. TH immunoreactive nerve bundles without varicosities and fibers with varicosities, associated or unassociated with blood vessels, were found in both the exocrine and endocrine pancreas. Close apposition of TH immunoreactive nerve fibers to the smooth muscle and endothelial cells of the blood vessels was observed. A close apposition between TH immunoreactive nerve fibers and exocrine acinar cells and islet endocrine cells was sometimes found in the pancreas. The immunoreaction product was seen diffusely in the axoplasm and in the granular vesicles of the immunoreactive nerve fibers. Since no TH immunoreactive ganglion cells were present in the rat pancreas, the present study suggests that noradrenergic nerve fibers in the pancreas may be extrinsic in origin, and may exert an effect on the regulation of blood flow and on the secretory activity of the acinar cells, duct cells and endocrine cells.
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PMID:Immunocytochemical study of tyrosine hydroxylase and dopamine beta-hydroxylase immunoreactivities in the rat pancreas. 752 36

Drug therapy for acute variceal bleeding should be viewed as an adjunct to emergency sclerotherapy. Its role in preventing very early rebleeding (within days) following sclerotherapy needs to be established. The best candidates for such a role are somatostatin and octreotide, but glypressin and vasopressin and nitroglycerin combinations have therapeutic effects in the short-term. Propranolol is the drug for long-term prevention of rebleeding and prevention of the first variceal bleed. For primary prophylaxis it significantly reduces the rate of bleeding, and there is a trend towards reducing mortality. It should be used in cirrhotic patients with large varices. For secondary prophylaxis, propranolol significantly reduces rebleeding but does not improve survival. The reduction in rebleeding is similar to long-term sclerotherapy when compared in randomized studies. There is no value in adding beta-blockers to sclerotherapy compared with sclerotherapy alone, but few studies have evaluated the effects after the eradication of varices. beta-Blockers can be used as the first-line therapy to prevent variceal rebleeding. They also have been shown to reduce the frequency of rebleeding from congestive gastropathy. Many patients do not have a portal pressure reduction with propranolol. The addition of isosorbide mononitrate converts many nonresponders to responders. Current clinical trials are evaluating if therapeutic efficacy is improved by these drug combinations.
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PMID:Pharmacological therapy for portal hypertension: rationale and results. 755 72


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