Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P01189 (beta-endorphin)
 21,003 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Brain-derived neurotrophic factor (BDNF) is a neurotrophin involved in neuronal survival and plasticity that binds to high-affinity receptors named TrkB. In the central nervous system, brain insults, including stress, induce modifications in BDNF messenger RNA (mRNA) expression. The present study attempted to determine in the adult rat pituitary, a peripheral structure relevant for the stress response: (1) whether BDNF and TrkB mRNA expression is influenced by different durations (15, 30, 60, 180 and 300 min) of single immobilization stress; (2) the expression of BDNF transcripts containing the different exons and their possible variations after stress exposure. Plasma corticotropin (ACTH) and corticosterone concentrations were strongly and significantly increased as early as 5 min after the stress stimulus. Using RNAse protection assay and in situ hybridization, a rapid increase in BDNF mRNA occurred at 15 min. This was accompanied by an increase in BDNF protein at 60 min, and by a rapid and significant decrease in TrkB mRNA expression observed at 15 and 30 min after stress application. RT-PCR analysis of BNDF transcripts showed strong basal expression of exons III and IV, whereas transcripts containing exons I and II seemed weakly expressed. After stress application, transcripts containing exons III and IV were rapidly and significantly increased at 30 min, whereas transcripts containing exons I and II remained unchanged. These results show that pituitary BDNF transcripts expression is differentially affected by immobilization stress.
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PMID:Immobilization stress rapidly and differentially modulates BDNF and TrkB mRNA expression in the pituitary gland of adult male rats. 1152 16

Brain-derived neurotrophic factor has been associated previously with the regulation of food intake. To help elucidate the role of this neurotrophin in weight regulation, we have generated conditional mutants in which brain-derived neurotrophic factor has been eliminated from the brain after birth through the use of the cre-loxP recombination system. Brain-derived neurotrophic factor conditional mutants were hyperactive after exposure to stressors and had higher levels of anxiety when evaluated in the light/dark exploration test. They also had mature onset obesity characterized by a dramatic 80-150% increase in body weight, increased linear growth, and elevated serum levels of leptin, insulin, glucose, and cholesterol. In addition, the mutants had an abnormal starvation response and elevated basal levels of POMC, an anorexigenic factor and the precursor for alpha-MSH. Our results demonstrate that brain derived neurotrophic factor has an essential maintenance function in the regulation of anxiety-related behavior and in food intake through central mediators in both the basal and fasted state.
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PMID:Conditional deletion of brain-derived neurotrophic factor in the postnatal brain leads to obesity and hyperactivity. 1157 7

Brain-derived neurotrophic factor (BDNF) is involved as an autocrine factor in the regulation of the secretory activity of the neuroendocrine pituitary melanotrope cells of Xenopus laevis. We studied the subcellular distribution of BDNF in Xenopus melanotropes using a combination of high-pressure freezing, cryosubstitution and immunoelectron microscopy. Presence of BDNF, pro-opiomelanocortin (POMC) and alpha-melanophore-stimulating hormone (alphaMSH) within melanotrope secretory granules was studied by triple-labelling immunoelectron microscopy. In addition, intracellular processing of BDNF was investigated by quantifying the number of immunogold particles in different stages of secretory granule maturation, in animals adapted to black or white background light conditions. The high-pressure freezing technique provides excellent preservation of both cellular ultrastructure and antigenicity. BDNF coexists with POMC and alphaMSH within secretory granules. BDNF-immunoreactivity increases along the secretory granule maturation axis (i.e. from electron-dense, via moderately electron-dense, to electron-lucent secretory granules). Immature, low immunoreactive, electron-dense secretory granules are assumed to contain mainly or even exclusively proBDNF. Strongly immunoreactive electron-lucent secretory granules represent the mature granule stage in which proBDNF has been processed to mature BDNF. Furthermore, in moderately electron-dense secretory granules, immunoreactivity is markedly (+79%) higher in black-adapted than in white-adapted animals, indicating that stimulation of melanotrope cell activity by the black background condition speeds up processing of BDNF from its precursor in this granule stage. It is concluded that, in the Xenopus melanotrope, BDNF biosynthesis and processing occur along the secretory granule maturation axis, together with that of POMC-derived alphaMSH, and that the environmental light condition not only controls the biosynthesis and secretion of BDNF and of POMC end-products, but also regulates the rate of their intragranular processing.
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PMID:Activity-dependent dynamics of coexisting brain-derived neurotrophic factor, pro-opiomelanocortin and alpha-melanophore-stimulating hormone in melanotrope cells of Xenopus laevis. 1496 71

Brain-derived neurotrophic factor (BDNF) is a key regulator of neuronal plasticity in adult rat brain and its effects are mediated through TrkB receptors. BDNF and its receptors are also localized in the pituitary, but their expressions throughout the rat lifespan are poorly known. Here we analyzed levels of BDNF and the different subtypes of TrkB receptors (mRNA and proteins) in the rat pituitary at different stages of life. BDNF immunoreactivity was expressed in folliculo-stellate cells from the anterior pituitary and in the intermediate lobe. TrkB.FL and TrkB.T1 receptors were strongly and essentially expressed in the intermediate lobe similar to the alpha-MSH localization pattern. These receptors begun decreasing at middle-age but TrkB.T2 was not detected in the pituitary at any age. Finally, in vitro alpha-MSH release from the intermediate lobe was correlated with the receptor content throughout the lifespan. The present results demonstrate the presence of BDNF in folliculo-stellate cells and indicated that receptors, rather than BDNF itself, are impaired with aging. These changes can contribute to explain age-dependent endocrine changes.
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PMID:Effect of aging on the expression of BDNF and TrkB isoforms in rat pituitary. 1676 56