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)

The localization of the somatostatin system in the brains of Richardson's ground squirrels (Spermophilus richardsonii) and European hedgehogs (Erinaceus europaeus) was described by use of immunocytochemical methods. In addition, (i) chemically differing types of somatostatin and (ii) different activity phases of the somatostatin system during the hibernation cycle were investigated in the ground squirrel by means of high pressure liquid chromatography (HPLC) and radioimmunoassay (RIA). In both species, the hypothalamic component of the somatostatin system (periventricular nuclei, fiber projections to the median eminence) is more prominent than the widespread extrahypothalamic representation of the system displaying mainly scattered perikarya and nerve fibers. The reactivity pattern of the somatostatin system varied among hibernating, aroused, and non-hibernating animals; moreover, the interspecific differences were pronounced. The activity of the hypothalamic somatostatin system in the hibernating ground squirrel appeared to be suppressed when compared to non-hibernating controls, whereas in the hibernating hedgehog this system showed signs of increased activity in comparison to non-hibernating controls. In contrast, in the present material the extrahypothalamic components of the somatostatin system did not exhibit significant changes in their activity.
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PMID:Effects of hibernation on somatostatin-like immunoreactivity in the brain of the ground squirrel (Spermophilus richardsonii) and European hedgehog (Erinaceus europaeus). 286 93

The morphology and distribution of somatostatinlike immunoreactive perikarya in the central nervous system of the hedgehog and sheep have been studied by means of the peroxidase-antiperoxidase immunohistochemical method. Intracerebroventricular colchicine infusion not only enhanced the immunostaining but also revealed new immunoreactive cell bodies. In both hedgehog and sheep immunoreactive neurons of various forms, ranging from 12 to 28 microns in diameter, were observed in a number of homologous brain structures. However, some species-related differences were noticed. Thus, somatostatinlike immunoreactive neurons were found only in the hedgehog anterior olfactory nucleus, olfactory tubercle, nucleus accumbens, medial parabrachial nucleus, raphe nuclei of the medulla, and spinal trigeminal nucleus, whereas some somatostatin-positive neurons were observed in the locus coeruleus and the pontine reticular formation of the sheep only. Mapping of peptides in species like sheep and hedgehog, with basically different orientations of living behaviour, may contribute in strengthening or extending our views concerning the role of peptides in the central nervous system of mammals.
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PMID:Somatostatinlike immunoreactive neurons in the hedgehog (Erinaceus europaeus) and the sheep (Ovis aries) central nervous system. 286 70

Fate determination in the mammalian forebrain, where mature phenotypes are often not achieved until postnatal stages of development, has been an elusive topic of study despite its relevance to neuropsychiatric disease. In the ventral telencephalon, major subgroups of cerebral cortical interneurons originate in the medial ganglionic eminence (MGE), where the signaling molecule sonic hedgehog (Shh) continues to be expressed during the period of neuronogenesis. To examine whether Shh regulates cortical interneuron specification, we studied mice harboring conditional mutations in Shh within the neural tube. At embryonic day 12.5, NestinCre:Shh(Fl/Fl) mutants have a relatively normal index of S-phase cells in the MGE, but many of these cells do not co-express the interneuron fate-determining gene Nkx2.1. This effect is reproduced by inhibiting Shh signaling in slice cultures, and the effect can be rescued in NestinCre:Shh(Fl/Fl) slices by the addition of exogenous Shh. By culturing MGE progenitors on a cortical feeder layer, cell fate analyses suggest that Shh signaling maintains Nkx2.1 expression and cortical interneuron fate determination by MGE progenitors. These results are corroborated by the examination of NestinCre:Shh(Fl/Fl) cortex at postnatal day 12, in which there is a dramatic reduction in cell profiles that express somatostatin or parvalbumin. By contrast, analyses of Dlx5/6Cre:Smoothened(Fl/Fl) mutant mice suggest that cell-autonomous hedgehog signaling is not crucial to the migration or differentiation of most cortical interneurons. These results combine in vitro and ex vivo analyses to link embryonic abnormalities in Shh signaling to postnatal alterations in cortical interneuron composition.
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PMID:Sonic hedgehog maintains the identity of cortical interneuron progenitors in the ventral telencephalon. 1622 24

The hypothalamus is a region of the anterior forebrain that controls basic aspects of vertebrate physiology, but the genes involved in its development are still poorly understood. Here, we investigate the function of the homeobox gene Rax/Rx in early hypothalamic development using a conditional targeted inactivation strategy in the mouse. We found that lack of Rax expression prior to embryonic day 8.5 (E8.5) caused a general underdevelopment of the hypothalamic neuroepithelium, while inactivation at later timepoints had little effect. The early absence of Rax impaired neurogenesis and prevented the expression of molecular markers of the dorsomedial hypothalamus, including neuropeptides Proopiomelanocortin and Somatostatin. Interestingly, the expression domains of genes expressed in the ventromedial hypothalamus and infundibulum invaded dorsal hypothalamic territory, showing that Rax is needed for the proper dorsoventral patterning of the developing medial hypothalamus. The phenotypes caused by the early loss of Rax are similar to those of eliminating the expression of the morphogen Sonic hedgehog (Shh) specifically from the hypothalamus. Consistent with this similarity in phenotypes, we observed that Shh and Rax are coexpressed in the rostral forebrain at late head fold stages and that loss of Rax caused a downregulation of Shh expression in the dorsomedial portion of the hypothalamus.
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PMID:Essential function of the transcription factor Rax in the early patterning of the mammalian hypothalamus. 2721 25