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)

A sensitive and specific radioimmunoassay (RIA) for arginine vasopressin (AVP) has been developed and validated. Synthetic AVP was coupled to bovine serum albumin (BSA) with glutaraldehyde. Antisera against AVP were raised in three rabbits immunized with AVP-BSA complex. After 6 months, at the 16th injection, one of the antisera had a titer high enough to be utilizable for RIA at a final dilution of 1:400,000. The labeling of AVP with 125I Na was performed with the modified chloramine T method, and the purification of iodinated AVP was done with gel filtration chromatography on a Sephadex G-25 fine column (1 X 20 cm) with an elution buffer of 0.01 M acetic acid containing 0.1% BSA. Radioactivities from the Sephadex G-25 were eluted in three peaks. 125I-AVP, which was reactive to the antiserum, was contained in the third peak, and 125I-AVP in the fractions on the down slope of the peak was used for the radioligand in the amount of 1000 cpm. The specific activity of purified 125I-AVP was about 400 muCi/microgram. Diluted antiserum and samples, unlabeled AVP or related peptides were preincubated at 4 degrees C for 24 hr, and then 125I-AVP was added to the mixture and incubated for a further 72 hr. Separation of B and F was done with polyethyleneglycol. The minimal detection limit of AVP, which was 95% of the confidence limit of the mean value of B0, was 0.4 pg/tube. The cross-reactivities with lysine vasopressin, arginine vasotocin, DDAVP and oxytocin were 0.1%, 30%, 1% and 0%, respectively. AVP in plasma was extracted with cold acetone and petroleum ether. The recoveries of synthetic AVP from plasma which was added (2-16 pg) were more than 94%. The intra and inter-assay coefficients of variation determined by plasma of AVP concentration of about 4.8 pg/ml were 8.7% and 11.3%, respectively. The RIA detected AVP of concentration as low as 1 pg/ml following the extraction procedure. AVP immunoreactivity was detected without extraction in urine, and the lyophilized cerebrospinal fluid and acid extract of tissues of the central nervous system, and the reactivities in these samples were demonstrated to be immunologically identical to that of synthetic AVP when diluted serially. The changes of plasma and urinary AVP concentration on water intake, water deprivation and smoking in humans were clearly demonstrated.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:[A sensitive and specific radioimmunoassay for arginine vasopressin and its validation]. 647 76

Extremely small amounts (10(-4) pg) of the pineal nonapeptide arginine vasotocin (AVT), injected into the pineal recess of freely moving cats, decreased the levels of 5-hydroxyindole acetic acid (5-HIAA) in the raphe dorsalis nucleus and induced slow wave sleep. In cats with lesions in the lateral habenula, 10(-4) pg AVT injected into the pineal recess, failed to decrease raphe dorsalis 5-HIAA levels and to induce slow wave sleep. The GABA antagonist picrotoxin (1 ng) injected into the pineal recess 15 min before the administration of AVT (10(-4) pg), completely prevented AVT from decreasing raphe dorsalis 5-HIAA levels and from inducing slow wave sleep. A highly significant correlation could be established between the decrease of raphe dorsalis 5-HIAA levels and the induction of slow wave sleep. No changes in raphe dorsalis 5-HIAA levels could be detected in cats injected with 10(-4) pg AVT into the lateral or into the fourth ventricle. Neither arginine vasopressin nor oxytocin (10(-4) pg) injected into the pineal recess, could alter raphe dorsalis 5-HIAA levels. It is concluded that AVT induces slow-wave sleep in cats by activating an inhibitory GABAergic lateral habenula-raphe dorsalis pathway.
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PMID:A GABAergic habenulo-raphe pathway mediates both serotoninergic and hypnogenic effects of vasotocin in cats. 651 96

Seventeen human fetal and neonatal pituitary glands were removed at necropsy, and analyzed for oxytocin content by a specific and sensitive radioimmunoassay, after homogenization in 0.4M acetic acid. Serial dilution of the pituitary extract showed parallelism with the oxytocin standard curve on the radioimmunoassay. Column chromatography of the pituitary gland extract gave a single peak of immunoreactive oxytocin as determined by the radioimmunoassay. In eight fetuses, 14 to 17 weeks' gestation, pituitary gland oxytocin was 10.2 +/- 5.9 ng/gland (mean +/- SE), whereas an 18-week fetus had 5.8 ng of oxytocin per gland. Pituitary gland oxytocin content increased to 38.4 ng/gland in a 20-week fetus removed at hysterectomy, and 31.6 ng/gland in a 26-week fetus. Fetal pituitary gland oxytocin values were 22.1 ng/gland and 57.0 ng/gland at 32 weeks and increased significantly to 544.3 +/- 33.8 ng/gland in 1- to 5-day-old term newborn infants (n = 3). However, a 13-day-old term newborn infant had 3.7 ng of oxytocin per pituitary gland. The increased pituitary gland oxytocin content with advancing gestation was due to a significant increase in oxytocin concentration rather than to an increase in the weight of the pituitary gland. The findings indicate that oxytocin is present in fetal pituitary glands as early as 14 to 17 weeks' gestation and increases at term to 50 and 13 to 14 times more than in early midtrimester and early third-trimester pregnancy, respectively.
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PMID:Oxytocin content of human fetal pituitary glands. 669

To determine if oxytocin (OT) is present in cynomolgus monkey corpus luteum, OT was measured by a specific and sensitive RIA in 13 corpora lutea, ovarian venous plasma on the ipsilateral side and peripheral venous plasma at different stages of the luteal phase. Serial dilution of acetic acid extract of the corpus luteum showed parallelism with standard OT in the RIA. Total content of OT in corpus luteum was 1.9 +/- 0.5 ng (mean +/- SEM) with a content of 0.4-0.8 ng in early luteal phase, 1.0-6.2 ng in midluteal phase, and 0.4-0.7 ng in late luteal phase. OT concentrations in corpus luteum were 21.0-75.2 ng/g wet wt in early luteal phase, increasing to 34.4-602.5 ng/g in midluteal phase; and declining to 3.4-117.4 ng/g in late luteal phase. OT concentrations per mg protein in the corpus luteum were 0.05-19.6 ng with peak concentrations of 14.7-19.6 ng/mg protein on day 22. Sephadex G-25 column chromatography of the corpus luteum extract revealed a single peak for binding activity similar to that of synthetic OT on the RIA. Ovarian vein blood from the same side as the corpus luteum had a significantly higher OT concentrations of 161.2 +/- 29.7 pg/ml on days 15-24 than 16.8 +/- 3.6 pg/ml on days 25-28 (P less than 0.01) and peripheral plasma OT levels of 23.2 +/- 3.4 pg/ml (P less than 0.025). Our findings indicate that OT is present and probably produced by monkey corpus luteum with peak OT concentrations found in midluteal phase. Thus OT may play a role in primate corpus luteum function.
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PMID:Oxytocin in the corpus luteum of the cynomolgus monkey (Macaca fascicularis). 674 70

Oxytocin was synthesized via the solid-phase method using dehydroalanine as pseudo-protecting group of the carboxyl-terminal as well as the omega-amide functions of asparagine and glutamine in endo-position. Starting with Boc-Gly-Dha-resin and using Boc-L-Asp(Dha-NHEt)-OH and Boc-L-Glu(Dha-NHEt)-OH as precursors of asparagine and glutamine, respectively, oxytocin was assembled in stepwise manner under solid phase synthesis conditions. Treatment of the protected [Glu(Dha-NHEt)4, Asp(Dha-NHEt)5]-oxytocin-Dha-resin with 1 n HCl in glacial acetic acid in the presence of 3 equiv. water removed the peptide from the support with the simultaneous formation of the asparagine and glutamine residues to give the protected nonapeptide amide: Cbz-Cys(Bzl)-Tyr(Bzl)-Ile-Gln-Asn-Cys(Bzl)-Pro-Leu-Gly-NH2, which was deprotected with sodium in liquid ammonia and then oxidized with diiodoethane to give oxytocin. After purification by gel chromatography and countercurrent distribution, the product displayed the chemical and physical properties and oxytocic activity (533 +/- 301U/mg) of a standard oxytocin preparation.
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PMID:Solid-phase synthesis of peptides via alpha, beta-unsaturated amino acids: oxytocin, simultaneous incorporation of amide functions in COOH-terminal and endo-positions. 711 12

Synthetic arginine-vasopressin (AVP), oxytocin (OXY) and arginine-vasotocin (AVT) were labelled with radioiodine at a moderate specific activity. The purity of the labelled octapeptides was checked by descendent paper chromatography in butanol-acetic acid-water (4 : 1 : 5 v/v) after a double filtration on a Sephadex G-25 column of the labelling mixtures. The rabbit anti-AVP serum bound 125I--AVP, the highest binding belling observed on the descendent eluates from the Sephadex column. The antiserum is specific to AVP, no binding being observed will AVT or oxytocin. The sensitivity of a RIA system using 125I--AVP, commercial anti-AVP serum and polyethyleneglycol separation technique, was of 5 pg/ml in terms of AVP with a biological activity of 385 IU/mg. The validity of the assay was tested on five patients (two with diabetes inspidus (DI) and three with other endocrine diseases) submitted to dehydration of hydration tests.
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PMID:Labelling of octapeptide neurohormones for in vitro studies. Radioimmunologic assay for arginine-vasopressin. 729 46

The general pharmacological properties of a novel cognition-enhancing agent, nefiracetam (N-(2,6-dimethylphenyl)-2-(2-oxo-1-pyrrolidinyl)acetamide, DM-9384, CAS 77191-36-7) were investigated, and the following results were obtained. 1. Central nervous system: Nefiracetam showed depressant activities (such as ataxia) on general behavior (mice), and inhibited spontaneous locomotor activity, rota-rod and traction performances (mice) and polysynaptic potential of the spinal reflex (rats), and potentiated pentobarbital anesthesia (mice). The drug inhibited electroshock-induced seizure at relatively low doses, but did not affect chemoshock-induced seizure (mice). Nefiracetam failed to show analgesic activity in the tail pinch test, but inhibited the acetic acid-induced writhing syndrome (mice). An inhibitory pattern in the electroencephalogram was observed (cats). Nefiracetam had little or no effect on body temperature (rats). 2. Respiratory and cardiovascular systems: Nefiracetam induced transient decreases in blood pressure, left ventricular pressure and LV dp/dt max at higher doses (dogs). 3. Autonomic nervous system: Nefiracetam had no influence on pupil size (rabbits). The drug induced no significant effect on the pressor response to norepinephrine or depressor response to acetylcholine, but inhibited the contractile response of the nictitating membrane to preganglionic cervical sympathetic nerve stimulation at the highest dose (dogs). 4. Gastrointestinal system: Nefiracetam inhibited gastrointestinal propulsion (mice), gastric emptying rate and gastric secretion (rats) at higher doses. Nefiracetam produced no apparent damage in the gastric mucosa, and had no effect on bile secretion (rats). 5. Isolated smooth muscle: Nefiracetam had no effect on the resting tonus of isolated ileum, whereas it inhibited the contractile response to acetylcholine, histamine, serotonin, nicotine and BaCl2 at higher concentrations (guinea pigs). Nefiracetam had no effect on the resting tonus or the serotonin-induced contraction of stomach fundus (rats). The drug had no effect on the resting tonus or the norepinephrine-induced contraction of vas deferens, but tended to inhibit the contraction induced by nerve stimulation (guinea pigs). Nefiracetam had little or no effect on the resting tonus or oxytocin-induced contraction of virgin uterus, or on spontaneous contraction of pregnant uterus (rats). Nefiracetam did not affect the resting tonus of trachea, whereas it inhibited isoproterenol-induced relaxation at the highest concentration (guinea pigs). Nefiracetam had no chronotropic effect in isolated atria, but showed a slight negative inotropic effect at the highest concentration (guinea pigs). 6. Miscellaneous: Nefiracetam slightly decreased urinary volume, whereas it did not affect urinary electrolyte excretion (rats).(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:General pharmacological profile of the new cognition-enhancing agent nefiracetam. 801 90

A 75-year-old female presented with a suprasellar granular cell tumor. Computed tomography (CT) revealed a high dense suprasellar mass with strong postcontrast enhancement. Magnetic resonance imaging showed a round suprasellar mass, which was hyperintense on the T1-weighted images with nonhomogeneous enhancement after the administration of gadolinium-diethylenetriaminepenta- acetic acid, and hypointense on the T2-weighted images. Cerebral angiography demonstrated no abnormal findings. The tumor was partially removed via a right frontotemporal craniotomy. The histological diagnosis was suprasellar granular cell tumor. Her postoperative course was uneventful other than mild and transient diabetes insipidus. She has remained asymptomatic without CT evidence of tumor regrowth for 20 months after the surgery. Immunohistochemical studies showed positive reaction for S-100 protein in the tumor cell nuclei, but no reaction for glial fibrillary acidic protein, neurofilament protein, Leu-7, oxytocin, beta-endorphin, adrenocorticotropic hormone, and vimentin. This case provides additional evidence for the astrocytic origin of suprasellar granular cell tumor.
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PMID:Suprasellar granular cell tumor. 874 Dec 54

Twenty days after bilateral adrenalectomy (ADX) or immediately after the last of three 6-h long immobilization periods, the levels of hypothalamic and neurohypophyseal L-[35S]Cys-labeled arginine vasopressin (AVP), oxytocin (OT), and somatostatin-14 (SRIF) (only stressed animals) were measured simultaneously in male Wistar rats, after third ventricular administration of the labeled precursor, via guide-cannulae. The acetic acid-extracted labeled peptide fractions were purified by two sequential HPLC steps. After a 4 h period of labeling, only L-[35S]Cys-AVP was selectively increased in the hypothalami of ADX-ized rats, compared to the sham-operated animals, possibly reflecting a significant activation of the paraventricular parvocellular (PVC) AVP/corticotropin-releasing factor (CRF) neurons. The increased accumulation of neurohypophyseal L-[35S]Cys-labeled AVP and OT in these animals, without changes in the endogenous levels of these peptides, as measured by UV absorbance, also suggests a moderate activation of the magnocellular (MGC) AVP and OT neurons, as a consequence of adrenal insufficiency. In response to immobilization stress, levels of L-[35S]Cys-OT were selectively increased in the hypothalami and corresponding neurohypophyses, 2 h and 4 h after receiving the label, concomitantly with a statistically significant reduction in the stores of OT in the neural lobes. AVP and SRIF biosynthesis remained unaffected by immobilization; the neurohypophyseal AVP stores likewise remained unchanged. These observations suggest the selective activation of MGC-OT neurons in response to chronic immobilization stress. Selective increases in hypothalamic L-[35S]Cys-AVP in ADX-ized rats, and in hypothalamic L-[35S]Cys-OT in chronically stress-immobilized rats, are presented as a measure of PVC-AVP/CRF and MGC-OT neuronal activation, respectively.
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PMID:Vasopressinergic, oxytocinergic, and somatostatinergic neuronal activity after adrenalectomy and immobilization stress. 956 8

The pharmacological effects of the aqueous extract of Neorautanenia mitis (family Papilonaceae) were studied in rodents. Investigations were carried out on acetic acid-induced writhing (pain) in mice and hind paw oedema in rats. The effects of the extract were also studied on the isolated non-pregnant rat uterus and rabbit jejunum. Results showed the extract to possess significant (P<0.05) dose-dependent anti-nociceptive activity between 12.5 and 50.0 mg/kg p.o. in mice and slight anti-inflammatory activity at 25 and 50 mg/kg p.o. in rats. The extract also produced a concentration-dependent inhibition of the normal rhythmic contraction of the isolated non-pregnant rat uterus. It was found to inhibit oxytocin-induced as well as acetylcholine-induced contractions in the rat uterus. The extract also exhibited concentration-dependent inhibition of spontaneous contractions of the rabbit jejunum. Preliminary phytochemical analysis of the extract revealed the presence of saponin glycosides, flavonoids, tannins and alkaloids. The extract had an intraperitoneal (i.p.) LD(50) of 282.84+/-3.2 mg/kg in mice. These data corroborate the traditional use of this plant in the treatment of dysmenorrhea.
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PMID:Pharmacological effects of the aqueous extract of Neorautanenia mitis in rodents. 1096 73


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