Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P01178 (oxytocin)
 15,767 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Although the suprachiasmatic nuclei (SCN) have been intensively analyzed, they contain a population of cells that has not yet been characterized. In this study, we examined the distribution of cells immunoreactive (ir) for calbindin-D28K (CaBP), calretinin (CR), parvalbumin, vasopressin-associated neurophysin (NP), substance P (SP), vasoactive intestinal peptide (VIP), and light-induced Fos-like protein. Previously unidentified cells in the core of the hamster SCN contained CaBP. Photic stimulation during the night induced Fos expression in about 75% of the CaBP-positive SCN cells, and about 50% of the Fos-positive cells in the core region expressed CaBP. These findings provide new information in the search for the cellular localization of pacemaker cells in the SCN, as photic input entrains the circadian system, and cells that receive photic input must be either part of the clock itself, or an upstream component of the clock.
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PMID:Calbindin-D28K cells in the hamster SCN express light-induced Fos. 881 37

By use of a double-labeling immunofluorescence method with a confocal laser scanning microscope, we have examined whether a calcium-binding protein, calretinin, is localized in magnocellular oxytocin and vasopressin neurons of the rat hypothalamus. In the supraoptic nucleus, all oxytocin-labeled cells were stained for calretinin. However, in the magnocellular part of the paraventricular nucleus, almost all oxytocin-stained cells were devoid of calretinin immunoreactivity. All vasopressin-positive cells of both the supraoptic nucleus and the magnocellular part of the paraventricular nucleus lacked calretinin immunoreactivity. No calretinin immunoreactivity was found in oxytocin-labeled cells of the the anterior commissural nucleus or in vasopressin-labeled cells of the suprachiasmatic nucleus. We previously showed that another calcium-binding protein, calbindin-D28k, was localized in magnocellular oxytocin neurons of the supraoptic nucleus but not in those of the paraventricular nucleus. These findings suggest that, in general, magnocellular oxytocin neurons of the supraoptic nucleus and those of the paraventricular nucleus can be chemically distinguished, that is, the former contain both calretinin and calbindin-D28k but the latter lack the two calcium-binding proteins.
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PMID:Calretinin is differentially localized in magnocellular oxytocin neurons of the rat hypothalamus. A double-labeling immunofluorescence study. 890 81

Recent electrophysiological experiments, in which purified calbindin-D28k (calbindin) and calretinin antibodies were diffused into these neurons, showed that Ca2+-dependent membrane potentials and firing patterns were profoundly and predictably affected by Ca2+-binding proteins (CaBPs). The present study used quantitative analyses of a dual-labeling immunofluorescence method to investigate the colocalization of the CaBPs, calbindin and calretinin in oxytocin (OT)- and (VP)-containing neurons of the supraoptic nucleus. Analyses of tissue immunostained with two different dilutions of each CaBP antibody used, revealed that 84% and 72% of the OT neurons were positive for calbindin immunoreactivity (-ir) at the higher and lower antibody concentrations, respectively. 52% and 50% of OT neurons were positive for calretinin-ir; thus, many OT neurons express both calbindin and calretinin. In contrast, only 25% and 18% of VP neurons showed calbindin-ir, and they were virtually devoid of calretinin-ir. These results provide evidence that CaBP expression in OT neurons is both greater and more diverse than in VP neurons, and are consistent with the hypothesis that Ca2+ buffering capacity contributes to the control of intrinsic firing patterns.
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PMID:Colocalization of calretinin and calbindin-D28k with oxytocin and vasopressin in rat supraoptic nucleus neurons: a quantitative study. 952 78

The aim of the present study was to examine quantitatively whether two calcium-binding proteins, calbindin D28k and calretinin, are localized in oxytocin and vasopressin neurons of the supraoptic nucleus of the male rat. We used a triple-labeling immunofluorescence method with a confocal laser scanning microscope. Of the oxytocin-labeled cells, 70% were stained for both calbindin D28k and calretinin, 15% were stained for only calbindin D28k, 13% were stained for only calretinin, and 2% were stained for neither protein. Of the vasopressin-labeled cells, 73% were stained for neither calbindin D28k nor calretinin, 21% were stained for only calbindin D28k, 4% were stained for only calretinin, and 2% were stained for both proteins. Calbindin D28k and calretinin have been shown previously to contribute to calcium homeostasis by buffering [Ca(2+)](i). Therefore, these findings suggest that most of the oxytocin neurons may have a higher Ca(2+)-buffering capacity than most of the vasopressin neurons.
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PMID:Calbindin D28k and calretinin in oxytocin and vasopressin neurons of the rat supraoptic nucleus.A triple-labeling immunofluorescence study 1050 16

The aim of the present study was to examine quantitatively whether two calcium-binding proteins, calbindin D28k and calretinin, are localized in oxytocin and vasopressin neurons of the supraoptic nucleus of the male rat. We used a triple-labeling immunofluorescence method with a confocal laser scanning microscope. Of the oxytocin-labeled cells, 70% were stained for both calbindin D28k and calretinin, 15% were stained for only calbindin D28k, 13% were stained for only calretinin, and 2% were stained for neither protein. Of the vasopressin-labeled cells, 73% were stained for neither calbindin D28k nor calretinin, 21% were stained for only calbindin D28k, 4% were stained for only calretinin, and 2% were stained for both proteins. Calbindin D28k and calretinin have been shown previously to contribute to calcium homeostasis by buffering [Ca2+]i. Therefore, these findings suggest that most of the oxytocin neurons may have a higher Ca(2+)-buffering capacity than most of the vasopressin neurons.
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PMID:Calbindin D28k and calretinin in oxytocin and vasopressin neurons of the rat supraoptic nucleus. A triple-labeling immunofluorescence study. 1055 35

Ca(2+) binding proteins (CaBPs), calbindin-D(28k) (calbindin) and calretinin, are thought to contribute to the regulation of intracellular Ca(2+) in many neuronal populations and perhaps more importantly, signal functional modulation in neuronal activity. In the present experiments, light microscopic immunohistochemistry revealed that the immunoreactivity of calbindin and calretinin was contained in varicose axons in the posterior pituitary. The dual labeling study with confocal microscopy demonstrated that calbindin immunoreactivity was present in the terminals of both oxytocin (OXT) and arginine-vasopressin (AVP) neurons. However, calretinin immunoreactivity was exclusively seen in the OXT terminals. Moreover, the dual labeling study showed that most calretinin-positive terminals contained calbindin immunoreactivity, demonstrating the colocalization of calbindin and calretinin in the same OXT nerve terminals. By electron microscopy, calbindin and calretinin immunoreactivities were seen in the neurosecretory axons and nerve terminals. These immunoreactive nerve terminals were seen to contain more clear microvesicles than dense-core neurosecretory granules. This immunoelectron microscopic observation suggests that both calbindin and calretinin localize preferentially in the active zone of the nerve terminals, which usually face the perivascular space around fenestrated capillaries. In spite of similar localization of calbindin and calretinin within the posterior pituitary, Western blot analysis showed some differences between the two CaBPs. Calbindin was present mostly in the soluble fraction with little in the insoluble fraction, but a substantial portion of calretinin was present in both the insoluble and soluble fractions. Moreover, dehydration induced by drinking 2% NaCl solution and deprivation of drinking water increased calretinin levels in the posterior pituitary as compared with control, but the calbindin level was not changed. The present findings demonstrate that calbindin and calretinin colocalize in the active zones of OXT nerve terminals, but only calretinin is upregulated with dehydration, suggesting different physiological role of calbindin and calretinin in the nerve terminals.
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PMID:Calbindin-D28k and calretinin in the rat posterior pituitary; light and electron microscopic localization and upregulation with dehydration. 1106 30

Arginine vasopressin- (AVP) and oxytocin- (OXT) secreting magnocellular neurons undergo gross structural changes with chronic physiological stimulation. Here, we investigated subcellular aspects of plasticity in rat neurohypophysial terminals during dehydration. Ultrastructural analyses demonstrated that chronic dehydration by 2% NaCl drinking for 7 days significantly decreased the numbers of neurosecretory granules and microvesicles but not the numbers of mitochondria. Moreover, in dehydrated rats, terminals making neurovascular contacts enlarged, whereas terminals in apposition to astrocytes, i.e., neuroglial contacts, became smaller. Western blot analyses demonstrated significant decreases in the levels of F3 and Thy-1 together with those of AVP- and OXT-neurophysin, but the levels of synaptophysin, SNAP-25, and GAP-43 were unchanged. Both F3 and Thy-1 were recovered in the buffer-insoluble pellet, and phosphatidyl inositol-specific phospholipase C treatment released both molecules from the crude membrane fraction, indicating that they are attached to terminal membranes by glycosylphosphatidyl inositol anchors. Confocal microscopic observations demonstrated that F3 colocalized with Thy-1 in the same terminals of magnocellular neurons. In contrast, the level of calretinin, a Ca(2+) binding protein was significantly increased with chronic dehydration. Thus, the present results suggest that enhancement of neurovascular contacts results from rearrangement of terminal-astrocyte and terminal-vessel contacts rather than enlargement or sprouting of magnocellular terminals themselves. The down-regulation of F3 and Thy-1 may contribute to enhancement of neurovascular contacts that accompany increased peptide release during dehydration.
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PMID:Plasticity of neurohypophysial terminals with increased hormonal release during dehydration: ultrastructural and biochemical analyses. 1134 90

The organization of the human hypothalamus was studied in 33 brains aged from 9 weeks of gestation (w.g.) to newborn, using immunohistochemistry for parvalbumin, calbindin, calretinin, neuropeptide Y, neurophysin, growth-associated protein (GAP)-43, synaptophysin, and the glycoconjugate 3-fucosyl- N-acetyl-lactosamine. Developmental stages are described in relation to obstetric trimesters. The first trimester (morphogenetic periods 9-10 w.g. and 11-14 w.g.) is characterized by differentiating structures of the lateral hypothalamic zone, which give rise to the lateral hypothalamus (LH) and posterior hypothalamus. The PeF differentiates at 18 w.g. from LH neurons, which remain anchored in the perifornical position, whereas most of the LH cells are displaced laterally. A transient supramamillary nucleus was apparent at 14 w.g. but not after 16 w.g. As the ventromedial nucleus differentiated at 13-16 w.g., three principal parts, the ventrolateral part, the dorsomedial part, and the shell, were revealed by distribution of calbindin, calretinin, and GAP43 immunoreactivity. The second trimester (morphogenetic periods 15-17 w.g., 18-23 w.g., and 24-33 w.g.) is characterized by differentiation of the hypothalamic core, in which calbindin- positive neurons revealed the medial preoptic nucleus at 16 w.g. abutted laterally by the intermediate nucleus. The dorsomedial nucleus was clearly defined at 10 w.g. and consisted of compact and diffuse parts, an organization that was lost after 15 w.g. Differentiation of the medial mamillary body into lateral and medial was seen at 13-16 w.g. Late second trimester was marked by differentiation of periventricular zone structures, including suprachiasmatic, arcuate, and paraventricular nuclei. The subnuclear differentiation of these nuclei extends into the third trimester. The use of chemoarchitecture in the human fetus permitted the identification of interspecies nuclei homologies, which otherwise remain concealed in the cytoarchitecture.
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PMID:Organization of human hypothalamus in fetal development. 1195 31

We have studied the organization of the hypothalamus in an Australian diprotodontid metatherian mammal, the wallaby ( Macropus eugenii), using cytoarchitectural, histochemical and immunohistochemical techniques. Coronal sections of adult brains were processed for Nissl staining, histochemical reactivity (cytochrome oxidase, nicotinamide adenine dinucleotide phosphate diaphorase and acetylcholinesterase) and immunohistochemistry (antibodies to tyrosine hydroxylase, calbindin, calretinin, non-phosphorylated neurofilament protein, oxytocin and vasopressin). The distribution of immunoreactive neurons for these substances was mapped with the aid of a computer-linked microscope. In general, the wallaby hypothalamus showed a similar nuclear organization to that seen in rodents. The paraventricular nucleus could be divided into several subdivisions based on the different cellular parcellation, similar to that described in rodents. The ventromedial hypothalamic nucleus had cell-sparse dorsomedial and cell-dense ventrolateral subdivisions as seen in eutheria, suggesting a similar functional compartmentalization in all theria. The positions of tyrosine hydroxylase-positive neurons in the wallaby hypothalamus were also similar to those in eutheria. Oxytocin and vasopressinergic neurons were found in all the same major nuclear groups as seen in eutheria, although a nucleus circularis could not be identified. The general similarities between wallaby and eutherian hypothalamus indicate that the basic chemo- and cytoarchitectural features of the hypothalamus are common to eutheria and metatheria and validate the use of the wallaby as a mammalian model of wide applicability in investigations of hypothalamic functional development.
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PMID:Cyto- and chemoarchitecture of the hypothalamus of a wallaby ( Macropus eugenii) with special emphasis on oxytocin and vasopressinergic neurons. 1451 76

The organization of the human hypothalamus was studied in 31 brains aged from 9 weeks of gestation (w.g.) to newborn, using immunohistochemistry for parvalbumin, calbindin, calretinin, neuropeptideY, neurophysin, growth associated protein GAP43, synaptophysin and glycoconjugate, 3-fucosyl-N-acetyl-lactosamine. Morphogenetic periods 9-10 and 11-14 w.g. are characterized by differentiating structures of the lateral hypothalamic zone, which give rise to the lateral hypothalamus (LH) and posterior hypothalamus. The perifornical nucleus differentiates at 18 w.g., from LH neurons which remain anchored in the perifornical position while most of the LH cells are displaced laterally. A transient supramamillary nucleus was apparent at 14 w.g. but not after 16 w.g. As the ventromedial nucleus differentiated at 13-16 w.g., three principal parts; the ventrolateral, the dorsomedial and the shell were revealed by distribution of calbindin, calretinin and GAP43 immunoreactivity. Morphogenetic periods 15-17, 18-23 and 24-33 w.g. are characterized by differentiation of the hypothalamic core, in which calbindin positive neurons revealed the medial preoptic nucleus at 16 w.g. abutted laterally by the intermediate nucleus. The dorsomedial nucleus was clearly defined at 10 w.g. and consisted of compact and diffuse parts, an organization that was lost after 15 w.g. Differentiation of the medial mamillary body into lateral and medial was seen at 13-16 w.g. Morphogenetic period after 34 w.g. was marked by differentiation of midline zone structures including suprachiasmatic, arcuate and paraventricular nuclei. The findings of the present study provide for a better understanding of the structural organization of the adult human hypothalamus, produce new evidence for homologies with the better studied rat hypothalamus and underpin staging system for fetal human hypothalamic development.
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PMID:Hypothalamus of the human fetus. 1472 28


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