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)

Further immunocytochemical analysis of the neuroblasts with SRIF-like immunoreactivity (ir) was carried out on the chick embryo medulla and pons. 5 or 100 microns rombencephalon sections were obtained from 60 White Leghorn chick embryos at stages (E = Embryonic days) ranging from E4 1/2 to E18 and incubated with rabbit polyclonal antibodies against synthetic cyclic Somatostatin-14, according to PAP-DAB technique. In the medulla and pons the ir appeared as from E12. From E12 to E13 1/2-E14 the ir distribution gradually changed. From E14 to E18 numbers and spatial arrangement of the positive neuroblast groups did not show substantial changes; in these respects the ir distributional pattern proved to be markedly different from the one observed by the Authors in adult animals. Moreover, from E13 to E15 the positive neuroblast density appeared to be higher than that of positive neurons in adults. These results are consistent with a possible SRIF local regulative role.
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PMID:Further data on the development of SRIF-like immunoreactive nerve cell populations in the chick embryo brain stem. I. Medulla and pons. 136 Aug 1

Further immunocytochemical analysis of the neuroblasts with SRIF-like immunoreactivity (ir) was carried out on the chick embryo midbrain tegmentum. 5 or 100 microns mesencephalon sections were obtained from 60 White Leghorn chick embryos at stages (E = Embryonic days) ranging from E4 1/2 to E18 and incubated with rabbit polyclonal antibodies against synthetic cyclic Somatostatin-14, according to PAP-DAB technique. In the midbrain tegmentum the ir appeared as from E12. From E12 to E13 1/2-E14 the ir distribution gradually changed. From E14 to E18 numbers and spatial arrangement of the positive neuroblast groups did not show substantial changes; in these respects the ir distributional pattern proved to be similar to the one observed by the Authors in adult animals. From E17 to E18 a decrease in the positive neuroblast density appeared to occur, particularly in a ventrally placed group. These results are consistent with a possible local regulative role of the SRIF.
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PMID:Further data on the development of SRIF-like immunoreactive nerve cell populations in the chick embryo brain stem. II. Midbrain tegmentum. 136 Aug 2

The postnatal development of somatostatin (SRIF)-immunoreactive neurons, previously labeled with [3H]thymidine on embryonic days E14-E22, has been studied in the rat occipital cortex. Immunocytochemistry combined with autoradiography showed an "inside-out" maturation pattern. Only SRIF neurons generated at E14 were present in layer VI in newborn rats. Later generated SRIF neurons appeared progressively higher in the cortex until about postnatal day 12 when SRIF neurons from E21 appeared in layer II. At 2 weeks of age, therefore, all SRIF neurons from E14-E21 were present. Most of these had been generated between E15 and E17 with a moderate number at E14 and rapidly diminishing numbers from E18 to E21. Although an overall layered distribution was apparent at peak production, there was a tendency for diffuse distribution most noticeable at E17. Diffusely distributed neurons were more likely to be below their appropriate layer than above it, thus contributing extra SRIF neurons to layer VI. At 3, 4, and 5 weeks, progressively fewer SRIF neurons were seen with a consequent reduction in the number of double-labeled neurons. It is suggested that the transient population of SRIF neurons thus revealed plays a role in cortical development.
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PMID:Development of somatostatin immunoreactive neurons in the rat occipital cortex: a combined immunocytochemical-autoradiographic study. 289 82

Experiments utilizing a combination of [3H]thymidine autoradiography and immunohistochemistry were conducted to determine the time of origin of somatostatin-immunoreactive (SSIR) neurons in the hippocampal formation of the rat. A quantitative and topographic description of neurogenesis in this peptide-containing neuronal system was generated using a computer-aided system to plot the position of labeled cells. Dissected and 'flattened' hippocampal preparations were used to facilitate the analysis of spatial gradients of SSIR cell development. The results indicate that most SSIR hippocampal cells are generated during a short embryonic period which extends from the 12th through the 15th day of gestation (E12-E15). Within this period of development, the distribution of SSIR cells follows a spatial gradient along the transverse or subiculo-dentate axis of the hippocampus. The earliest formed SSIR neurons, generated on E12 and E13, are preferentially distributed to the subiculum, those generated on E14 are most commonly observed throughout the CA1-CA3 fields of the hippocampus and SSIR neurons which become postmitotic on E15 are more heavily represented in the hilar region of the dentate gyrus than cells born at other stages of development. There was no clear-cut neurogenic gradient along the septotemporal axis of the hippocampus. These results indicate that somatostatin cells in the rat hippocampal formation are generated during the same prenatal period when glutamic acid decarboxylase (GAD)-positive neurons become postmitotic. These studies also suggest that quantitative developmental analyses of chemically specific cell types can reveal prominent features of cortical ontogeny that are not readily apparent in standard [3H]thymidine preparations.
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PMID:The time of origin of somatostatin-immunoreactive neurons in the rat hippocampal formation. 290 62

Somatostatin immunoreactive (SOM-I) perikarya were first observed in the ventral horn at E12, in the presumptive intermediate gray area at E14, and in the alar plate of the rostral spinal cord at E14. In general, after their initial appearance, their density increased and then decreased during development. A moderate density of SOM-I varicosities became obvious in the superficial laminae of the E20 dorsal horn. By E12 a few SOM-I perikarya, interpreted to be dorsal root ganglia, were observed lateral to the spinal cord, and by E13, SOM immunoreactivity was visualized within the central and peripheral processes of dorsal root ganglion axons. In the marginal zone, SOM-I fibers were first demonstrable in the ventral funiculus at E14, and in the lateral funiculus at E15. After their initial appearance, their density increased and then decreased with age, with the exception of the dorsal part of the lateral funiculus where it increased at the early stages of development to an apparently stable level. The early detection of SOM immunoreactivity in specific spinal regions corresponds well with the birth dates of cells in those regions. This indicates that the SOM-I cells are capable of synthesizing the substance at least as early as they have entered their final cell division.
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PMID:Somatostatin immunoreactive structures in the developing rat spinal cord. 290 30

The differentiation of intracerebral and intraspinal transplants of fetal (E14-E15) rat spinal cord was studied to determine the extent to which myelin-free zones in these embryonic grafts exhibit cytological features and immunocytochemical characteristics of the substantia gelatinosa (SG) of the normal spinal cord. Immunocytochemical staining with antiserum to myelin basic protein (MBP) revealed myelin-free areas of varying proportions within fetal spinal cord grafts. These regions were identified in both newborn and adult recipients regardless of whether donor tissue was grafted to heterotopic (intracerebral) or homotopic (intraspinal) sites. As in the SG of the intact spinal cord, the myelin-free regions consisted mainly of small (7-15 microns) diameter neurons. At the ultrastructural level, these cells were surrounded by a neuropil composed of numerous small caliber, unmyelinated axons and intermediate-sized dendrites. Synaptic terminals in these areas were primarily characterized by the presence of clear, round vesicles, although granular vesicles were occasionally found within these terminals. Immunocytochemical staining demonstrated met- and leu-enkephalin-, neurotensin-, substance P-, and somatostatin-like immunoreactive elements within these myelin-free areas. Thus, regions within embryonic spinal cord grafts undergo some topographical differentiation which parallels that of the normal superficial dorsal horn. The presence of SG-like regions illustrates the potential capacity of fetal spinal cord transplants for replacing some intraspinal neuronal populations at the site of a spinal cord injury in neonatal and adult animals. These graft regions may serve as a source of intersegmental projection neurons or establish an extensive intrinsic circuitry similar to that seen in the normal SG. In addition, the definition of these areas provides a useful model to study the innervation patterns of host axons that typically project to the substantia gelatinosa of the normal spinal cord.
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PMID:Differentiation of substantia gelatinosa-like regions in intraspinal and intracerebral transplants of embryonic spinal cord tissue in the rat. 291 47

With hybridization histochemistry, somatostatin (SRIF) mRNA was detected in several neuronal populations of the basal diencephalon (anterior and posterior) and basal telencephalon (lateral) for the first time on the 14th day of gestation (E14). On E16, a large increase of the extent of expression was found in these populations. In addition, cells in the medial telencephalon and a few cells in the future allocortex also contained SRIF mRNA for the first time. In the prenatal period, the expression in the above populations continued to mature and individual nuclei with SRIF mRNA began to be recognizable. At birth, the overall pattern of SRIF gene expression was established but the ventral portions (hypothalamus, amygdala, allocortical areas) had higher levels of expression than the more dorsal ones (striatum and neocortex). Over the first 2 wk of life, this difference decreased and an adult-like pattern was found at postnatal day 21. We demonstrate that most of SRIF gene expression development takes place before birth. This description may serve as a basis for studies on the putative functions of SRIF during brain ontogeny.
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PMID:Ontogeny of somatostatin gene expression in rat forebrain. 791 43

Cyclic AMP (cAMP) mediates the hormonal stimulation of a number of eukaryotic genes by directing the protein kinase A (PK-A)-dependent phosphorylation of the transcription factor CREB. Somatostatin is one such gene known to be transcriptionally activated by cAMP via CREB. In view of the role somatostatin plays in the regulation of neocortical development, we examined the early expression of CREB mRNA and protein (from E10 to E14) in the rat neocortex by in situ hybridization and immunocytochemistry. mRNA for CREB was detected in all layers of the developing neocortex from E10 to E14. CREB immunoreactivity (CREB-IR) was also observed in most cortical cells by E10. However, the number of CREB-immunoreactive nuclei decreased thereafter, and on E14 there were immunoreactive cells only in the preplate. A moderate amount of somatostatin mRNA was observed on E16 in layer I, which is produced from the preplate. This stage specific expression of the CREB protein in the developing neuroepithelium suggests that by regulating transcription of some peptides including somatostatin, CREB plays a role in cortical development.
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PMID:A developmental study of cyclic AMP-response element binding protein (CREB) by in situ hybridization histochemistry and immunocytochemistry in the rat neocortex. 792 74

The normal development of somatostatin (SOM) expression in neurons of the chick ciliary ganglion and the effects of ciliary neuronotrophic factor (CNTF) on SOM induction in cultured ciliary ganglion neurons, were studied by immunocytochemical techniques. SOM immunoreactivity was first detectable in some neurons of the ganglion at embryonic day (E)8 and between E14 to hatch. 44-46% of the neuronal population contained the peptide. It was inferred that essentially all choroid neurons, which constitute 50% of the neuronal population, contain SOM. Culture studies indicated that CNTF supported both the SOM positive choroid neurons and the SOM negative ciliary neurons. Although CNTF was necessary for the survival and maturation of cultured ciliary ganglion neurons, it did not influence either the induction or maintenance of SOM expression in these neurons. CNTF may instead act as a permissive factor, allowing the induction of SOM in neurons of the ciliary ganglion by other, more specific, factors.
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PMID:Effect of ciliary neuronotrophic factor on somatostatin expression in chick ciliary ganglion neurons. 809 25

Previous studies have suggested that activin may serve as a neurodifferentiation factor regulating somatostatin expression in neurons of the avian ciliary ganglion (CG). As one aspect of examining the role of activin in CG development, we inquired whether any of the known activin receptors are expressed by developing CG neurons in vivo. In addition, we examined whether activin A mRNA is expressed in the choroid layer and iris of the chicken eye. Oligonucleotide primers were designed for the chicken activin receptor type IIA (cActR-IIA), type IIB (cActR-IIB), and activin A. In reverse-transcription-polymerase chain reaction (rtPCR), an appropriately sized product was amplified from CG cDNA using primers to the cActR-IIA but not the cActR-IIB. Sequencing confirmed the identity of the PCR product as a fragment of the cActR-IIA. It thus appears that mRNA for the type IIA but not the type IIB activin receptor is expressed in the chicken CG. An antisense strand digoxigenin-labeled riboprobe complimentary to a 358-bp portion of the cActR-IIA kinase region hybridized to cells within cryostat sections of embryonic CG. From E6.5-E18, hybridization of this probe appears to be specific for cells with a neuronal morphology. Using rtPCR with activin A-specific primers we detected activin mRNA in the choroid layer of E14 and E19 eyes, and from the iris at E14. Our results are consistent with a role for activin as a neurodifferentiation factor in vivo, and imply that within the CG, the cActR-IIA is specifically expressed by neurons, and that activin A is expressed in the targets of these neurons.
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PMID:Activin receptor mRNA expression by neurons of the avian ciliary ganglion. 898 61


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