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)

To determine whether propressophysin (vasopressin-neurophysin precursor) is present in human plasma, the nature of the immunoreactive neurophysin was characterized by gel filtration. When plasma samples obtained from six patients with the syndrome of inappropriate antidiuretic hormone secretion due to central nervous system disease were fractionated on a column of Sephadex G-50 in 0.2 N acetic acid, virtually all of the nicotine-stimulated neurophysin (NSN) immunoreactivity coeluted with 125I-labeled NSN. In contrast, gel filtration of plasma from six patients with oat cell carcinoma of the lung with ectopic vasopressin production consistently demonstrated, in addition, a peak of a higher molecular weight (HMW) form of neurophysin. This HMW neurophysin represented 8.7-29.4% of the total NSN immunoreactivity in plasma and its elution profile was not changed when chromatographed after incubation in 6 M urea. On sodium dodecyl sulfate-polyacrylamide gel electrophoresis, the HMW neurophysin ran in the 20,000-dalton area of the gel. A substantial portion of the HMW neurophysin appeared to be a glycoprotein judging from its binding to Concanavalin A. When the HMW neurophysin was incubated with trypsin, most of the immunoreactivity was converted into a smaller neurophysin which bound to a vasopressin-agarose column in a pH-dependent manner. Moreover, a definite peak of immunoreactive vasopressin appeared after the trypsin treatment. This peak coeluted with synthetic arginine vasopressin on gel filtration and had the characteristic affinity of vasopressin for neurophysin-agarose. These results indicate that propressophysin circulates in patients with oat cell carcinoma of the lung with ectopic vasopressin production and suggest that plasma propressophysin may be a marker for ectopic vasopressin production.
 ...
PMID:Propressophysin in human blood: a possible marker of ectopic vasopressin production. 608 1

mRNA encoding the vasopressin-neurophysin precursor was quantitated in individual hypothalamic nuclei of rats by a liquid hybridization assay. Drinking of 2% saline for 14 days, a treatment that increased the plasma vasopressin concentration 9-fold, resulted in a 5- and 2-fold increase in mRNA levels in the supraoptic and paraventricular nucleus, respectively. This osmotic stimulus had no effect on vasopressin-neurophysin mRNA content of the suprachiasmatic nucleus. This dissociation in regulation of vasopressin-neurophysin mRNA in hypothalamic nuclei indicates the existence of two separate vasopressin systems that are independently activated.
 ...
PMID:Differential responses to osmotic stress of vasopressin-neurophysin mRNA in hypothalamic nuclei. 651 39

The molecular recognition hypothesis for peptides is that binding sites of ligands and their receptors are encoded by short, complementary segments of DNA. A corollary hypothesis for nonpeptide ligands posited here is that peptide replicas may be encoded by the DNA segment complementary to the receptor binding sites for nonpeptides. This corollary was tested for digitalis. a family of cardiotonic and natriuretic steroids including ouabain. A hexapeptide (ouabain-like peptide, OLP) complementary to a ouabain binding site on sodium potassium dependent adenosine triphosphatase (Na+ K+ ATPase) exhibited activity in a digitalis bioassay. Antisera to the complementary peptide (OLP) stained the neurohypophysis in an immunocytochemical procedure. The complementary peptide was found to share an identical 4-amino acid region with the 39-amino acid glycopeptide moiety of the vasopressin-neurophysin precursor. This glycopeptide was isolated from pituitary extracts; it exhibited digitalis-like activity in the submicromolar range and cross-reacted with complementary peptide antibodies. Another digitalis-like substance with high activity also was detected in the extracts. These results demonstrate that the vasopressin-neurophysin glycopeptide has digitalis-like activity. Moreover, the findings are consistent with the hypothesis that peptide mimetics of nonpeptides are encoded in the genome.
 ...
PMID:A molecular recognition hypothesis for nonpeptides: Na+ K+ ATPase and endogenous digitalis-like peptides. 1035 21