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

Large Gomori-positive cells were observed in rat thymus after hormonal induction (e. g. after treatment with oxytocin or hydrocortisone). In contrast to some findings by others, no evidence on endocrine function of these cells was found and they were identified as macrophages containing, in their cytoplasm, great amount of phagocytized material.
 ...
PMID:Gomori-positive cells in rat thymus: Lack of evidence on endocrine function. 108 Oct 47

In order to clarify the biological activities of (-)-oxetanocin G, and (-)-oxetanocin A and its carbocyclic analogue, (-)-carboxetanocin G, the inhibitory effects of triphosphate derivatives of these compounds (OXT-GTP, OXT-ATP, and C-OXT-GTP) on eukaryotic and viral DNA polymerases were examined. DNA polymerase alpha purified from calf thymus was weakly inhibited by OXT-GTP and OXT-ATP but strongly by C-OXT-GTP, the Ki value being 0.22 microM. On the other hand, rat DNA polymerase beta was not affected by these analogues. DNA polymerase gamma purified from bovine testes was very weakly inhibited by OXT-GTP and OXT-ATP, but not by C-OXT-GTP. DNA polymerase from herpes simplex virus type-II (HSV-II) was strongly inhibited by all three analogues, the Ki values ranging from 0.5 to 1.0 microM. Human immunodeficiency virus-encoded reverse transcriptase (HIV RT) was also strongly inhibited by these three analogues, the Ki value of C-OXT-GTP being slightly smaller than that of OXT-GTP or OXT-ATP. Analysis of products synthesized on singly primed M13 single-stranded DNA by DNA polymerase alpha, HSV-II DNA polymerase or HIV RT in the presence of the analogues revealed that OXT-GTP and C-OXT-GTP were incorporated into DNA and caused chain termination mainly at sites one or two nucleotides beyond the cytosine bases on the template.
 ...
PMID:Inhibitory effects of triphosphate derivatives of oxetanocin G and related compounds on eukaryotic and viral DNA polymerases and human immunodeficiency virus reverse transcriptase. 138 92

Monoclonal antibodies to oxytocin (OT) and vasopressin (VP) revealed some positively staining stromal cells in the subcapsular cortex and in the medulla of the human thymus. We further demonstrated that these cells are a subset of epithelial endocrine cells and also contain immunoreactive interleukin-1 together with the neuropeptides. In addition, the thymic cells stained by monoclonal antibodies directed to the cyclic part of oxytocin or vasopressin also contained some immunoreactive neurophysins. These data support the concept of intrathymic synthesis of neurohypophyseal-like peptides fitting the hypothalamic model. However, we observed that, contrary to the situation in the brain, OT- and VP-like peptides colocalized in the same thymic cells. Furthermore, one monoclonal antibody, specific for the tail part of oxytocin, did not label thymic cells. Therefore, thymic neuropeptide(s) could be related to, but distinct from, authentic OT and VP. These observations suggest some molecular differences between hypothalamic and thymic oxytocin biosynthetic pathways which need to be further investigated.
 ...
PMID:Colocalization of immunoreactive oxytocin, vasopressin and interleukin-1 in human thymic epithelial neuroendocrine cells. 171 50

Prenatal plus neonatal administration of methimazole (MMI), a procedure provoking marked hypothyroidism in rats, increased by about 100% the thymic content of oxytocin and severely (by approximately 80%) decreased the thymus weight, compared to euthyroid counterparts. Adult-onset, propylthiouracyl (PTU)-induced hypothyroidism, while provoking thymic involution, or thyroxine (T4) hyperthyroidism, did not affect oxytocin concentrations. Thymic involution and increases in thymus oxytoxin could also be obtained with repeated administration of the potent glucocorticoid dexamethasone. However, since corticosterone, unless subchronically injected at largely supraphysiological doses, was previously shown to have no influence on thymic parameters of young adult rats, a major involvement of the neonatal adrenal axis in oxytocin alterations could be excluded. It is suggested that the ontogenesis of thymic oxytocin production is under thyroid control.
 ...
PMID:Effects of neonatal and adult thyroid dysfunction on thymic oxytocin. 212 6

Receptor sites for the neurohypophyseal peptides arginine vasopressin (AVP) and oxytocin (OT) have been identified and characterized in some tissues involved in immune function in the rat. Novel radioiodinated ligands for the detection of neurohypophyseal hormone receptors, with a high specific radioactivity and affinity, enabled the selective detection of OT receptors in the thymus and vasopressin (VP) receptors in the spleen. OT receptors were detected in thymic membrane preparations and on thymocytes, which had a ligand selectivity similar to that of uterine OT receptors. AVP receptors of the V1 pressor type were present in a splenic membrane preparation. Specific AVP-binding sites, probably of the V1 type, were also present on splenic lymphocytes. Binding sites for AVP and OT could not be detected on mononuclear cells in peripheral blood of the rat. This study demonstrates that the use of the newly developed radioiodinated AVP and OT receptor ligands, with high specific radioactivity and affinity, enables the selective characterization of receptor sites for the neurohypophyseal hormones, even in the thymus, where previously no binding sites could be detected.
 ...
PMID:Neurohypophyseal hormone receptors in the rat thymus, spleen, and lymphocytes. 215 33

Immunoreactive oxytocin was determined in a peptidic extract of rat thymus by means of a highly specific radioimmunoassay combined with high pressure liquid chromatography fractionation. Rat thymus was found to contain 80 +/- 7.5 pg/g wet tissue (congruent to 0.56 pg/mg protein) of oxytocin-like immunoreactivity, which behaved like synthetic oxytocin in the radioimmunoassay and in two different high pressure liquid chromatography columns. Oxytocin concentration was increased by bilateral electrolytic lesion of the paraventricular nucleus of the hypothalamus (PVN), and by high doses of corticosterone (10 mg/kg IM for 7 days) but was not modified by low doses of corticosterone (1 mg/kg IM for 7 days) or by hypophysectomy. The results suggest that rat thymus synthesizes oxytocin and that thymic oxytocin concentration is modulated by the hypothalamus.
 ...
PMID:Hypothalamic modulation of immunoreactive oxytocin in the rat thymus. 238 74

Certain subtypes of thymic epithelial cells--the medullary epithelium, the cortical surface epithelium, and some intracortical epithelial cells--show strong immunohistochemical reactivity with antisera against oxytocin, Arg-vasopressin and neurophysin. The epithelial nature of the neuropeptide containing cells is shown by their morphology and their reactivity with monoclonal anti-cytokeratin AE1/E3. Hassall's corpuscles are positive as well. The immunoreactivity patterns for the three neuropeptides are identical, suggesting a parallel distribution. The vast majority of cortical epithelial cells are negative, emphasizing the tightly controlled microenvironment for T-cell development. The possibility of a neuroendocrine role of the thymus is discussed.
 ...
PMID:The neuroendocrine thymus. Abundant occurrence of oxytocin-, vasopressin-, and neurophysin-like peptides in epithelial cells. 245 71

A complex pattern of interactions appears to exist between the immune and neuroendocrine systems. Recently, vasopressin, oxytocin and vasoactive intestinal peptide have been isolated from the thymus. Using a rat somatostatin antisense RNA probe we have demonstrated expression of the somatostatin gene in the rat thymus. Furthermore, we have shown that the levels of thymic somatostatin mRNA exhibit a bell-shaped response to dexamethasone administration. Lipocortin I and II antisense RNA probes have been used as a positive control for the effects of the dexamethasone. We would suggest that somatostatin acts in the thymus in a paracrine mode to modulate T lymphocyte development.
 ...
PMID:Somatostatin gene expression in the thymus gland. 256 79

The neuropeptides oxytocin (OT) and vasopressin (VP) are synthesized in the human thymus in a similar way as in the hypothalamo-neurophypophyseal system. Immunocytochemistry with polyclonal and monoclonal antibodies revealed that immunoreactive OT- and VP-producing cells are localized in the subcapsular cortex and medulla of human and murine thymuses. The epithelial nature of the neuroendocrine thymic cells is demonstrated by their immunostaining with a monoclonal antibody against cytokeratin. An original example of a neuroendocrine-immune microenvironment is given by the thymic nurse cells which are composed of a large neuroendocrine epithelial cell enclosing numerous mitotic immature thymocytes. These observations and the previously reported mitogenic and immunomodulatory properties of VP and OT upon mature T cells and thymocytes strongly support the existence of a neuroendocrine thymo-lymphoid axis and an active role of thymic VP and OT in T cell differentiation and activation.
 ...
PMID:Neuroendocrinology of the thymus. 265 71

Thymic neuroendocrine cells were identified by immunofluorescence in the murine thymus through the use of monoclonal antibody A2B5, and specific polyclonal antisera against neurophysin (NP), oxytocin (OT) and arginine vasopressin (AVP). Two reactive regions were clearly identified: the subcapsular cortex and the medulla. A close correspondence was observed between A2B5-reactive and NP-immunoreactive cells in the medulla. An important epithelial population of the subcapsular cortex, the thymic nurse cells (TNCs), were found to be A2B5-positive and to contain immunoreactive NP, OT and AVP. The neuroendocrine nature of TNCs was further substantiated by their high reactivity with an antiserum against neuron-specific enolase. These observations demonstrate the presence in the thymus gland of an original neuroendocrine microenvironment which could be of functional importance in the mediation of central influences upon T lymphocyte differentiation.
 ...
PMID:The neurohormonal thymic microenvironment: immunocytochemical evidence that thymic nurse cells are neuroendocrine cells. 337 62


1 2 3 4 Next >>