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)

Lysine vasopressin- and oxytocin-encoding mRNAs have been analysed in the developing hypothalamus of the pig. The two hormone-encoding mRNAs were first detectable on fetal day 49 by Northern blot analysis. Whereas RNase mapping revealed identical transcripts throughout the developmental stages studied, Northern blots showed that the early transcripts appeared to be shorter (by 100-200 nucleotides) and more heterogeneous in size than those of later stages. This developmentally related length polymorphism was shown to be due to different poly(A) lengths and was abolished by removal of the poly(A) tails with RNase H. These results indicate that maturation of neurones in the developing porcine hypothalamus is accompanied by an increase in length of the poly(A) tail of vasopressin and oxytocin mRNAs.
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PMID:Poly(A) tail length of oxytocin- and lysine vasopressin-encoding mRNAs increases during development in the porcine hypothalamus. 197 13

Earlier studies indicate that rat hypothalamic oxytocin (OT) mRNA accumulation rises gradually during pregnancy and remains elevated throughout the lactation period. Here we show that, in addition, hypothalamic OT mRNA undergoes a structural change during this period. On gel electrophoresis, the size of rat OT mRNA increased from 750 bases (control) to a maximum of 820 bases (7th day of lactation). Removal of the poly(A) tail by the RNase H methods revealed that this size increase can be fully accounted for by a prolongation of the polyadenylate tail. There is considerable evidence for a role of the poly(A) tail segment in augmenting mRNA stability and, possibly, translational efficiency. It is thus conceivable that the demonstrated regulation of OT mRNA poly(A) tail length represents an additional level of OT gene control during pregnancy and lactation.
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PMID:Oxytocin mRNA: increase of polyadenylate tail size during pregnancy and lactation. 257 Jul 20

In the normal (Wistar) rat vasopressin encoding mRNA first appears at embryonic day 15 as demonstrated by in situ hybridization of hypothalamic sections. In mutant (Brattleboro) rats, which possess a defective vasopressin gene with a single nucleotide deletion, the corresponding transcript is not detectable before fetal day 18. In both rat strains however expression of the structurally related oxytocin gene begins at fetal day 19. Whereas normal and mutant vasopressin encoding mRNAs are identical in size up to at least three weeks after birth, the corresponding transcripts from adult Brattleboro but not from normal rats are markedly larger. This increase in size is due to a longer stretch of poly(A) sequence as demonstrated by treatment of the respective mRNAs with RNase H and oligo(dT). Thus the mutant vasopressin gene transcript is subject to a cellular-specific differential polyadenylation process during development.
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PMID:Differential polyadenylation of the mutant vasopressin mRNA during development of Brattleboro rats. 291 1

3' phosphorothioate modified sense or antisense oligonucleotides to oxytocin transcripts were used for in vivo targeting of oxytocin (OT) neurons in the rat hypothalamus. Intracerebroventricular injections of antisense probe resulted in a loss of systemic OT. However, abundant immunoreactive OT as well as oxytocin mRNA hybridization signal was visualized in the hypothalamo neurohypophysial system (HNS) of these animals. RT-PCR of hypothalamic homogenates revealed clearly detectable amounts of cytoplasmic OT mRNA in spite of sense or antisense treatment. Immunostaining with an antibody to DNA-RNA triple helix resulted in cytoplasmic reaction product in the HNS in the antisense group, which was not found when tissue sections had been pretreated with RNase. Animals injected with the sense probe showed a less pronounced but significant loss of systemic OT while immunoreactivity for this peptide in the posterior lobe seemed to be unaffected. RT-PCR of OT encoding mRNA extracted from sense injected rats indicated that these transcripts were of smaller size than samples from antisense treated animals or controls. Immunostaining with the triple helix antibody revealed distinct immunoreactive dots in cellular nuclei throughout the brain in the sense group. Our findings suggest that sense and antisense probes may not readily be employed as "functional antagonists" since peptidergic neurons are probably capable of responding in various ways to the treatment. RNase H may be less important in hypothalamic neurons as commonly suggested. Targeted transcripts are likely to form complexes which may somehow interact with secretion. Triple helix formation in the nucleus may not be able to induce an efficient transcriptional arrest. Although endocrine and behavioral changes observed in antisense treated animals seem to confirm the hypothesis that a selective translational "knock out" can be achieved with in vivo hybridization strategies, the actual underlying molecular events are far from being understood. On the other hand, sense or antisense strategies may provide valuable insights into molecular and cellular events associated with neurosecretion.
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PMID:Sense- and antisense-targeting of oxytocinergic systems in the rat hypothalamus. 871 52

Intracerebroventricular injections of oligonucleotide probes complementary to oxytocin mRNA are known to decrease systemic oxytocin levels. In this study we show that immunoreactive oxytocin in the magnocellular hypothalamic perikarya and in their neurohypophysial projections remains unaffected by intracerebroventricular injections with an oxytocin antisense probe in rats. Hybridization signal for oxytocin mRNA was increased in the supraoptic and paraventricular nuclei in these animals. Immunocytochemistry with a monoclonal antibody, raised against triple helical DNA resulted in an accumulation of cytoplasmic reaction product in many of the magnocellular oxytocin immunoreactive neurons and in a fraction of the Herring bodies inthe posterior pituitary lobe in the antisense treated rats. Such immunostaining could be abolished by pretreating sections with RNase H. Animals injected with a mismatch probe instead of the antisense probe were devoid of cytoplasmic or axonal triple helix immunostaining. Our findings indicate that oxytocinergic transcripts in magnocellular hypothalamic neurons form triple helix-like aggregates upon specific antisense targeting rather than being degraded by endogenous RNases. While de novo transcription of oxytocin is probably stimulated, systemic release of the nonapeptide may be impaired.
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PMID:Antisense targeting of oxytocinergic hypothalamus neurons induces cytoplasmic triple helix-like immunoreactivity. 1499 79