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)

Cerebrospinal fluid (CSF) samples were collected at frequent intervals (every 10-15 min) to determine if oxytocin pulses were present in the CSF of monkeys. Temporary indwelling subarachnoid catheters, with the tip of the catheter at the T12-L1 subarachnoid space, were placed in 4 nonlactating and 3 lactating (4 months post partum) female monkeys. Monkeys were maintained on jacket/tether/swivel systems in a constant photoperiod (07.00-19.00 h). CSF was continuously withdrawn at a rate of 1.2 ml/h by peristaltic pump, and CSF was collected in 15-min fractions (from 3 lactating monkeys and 1 nonlactating monkey) or in 10-min fractions (from the other 3 nonlactating monkeys) using a fraction collector. CSF oxytocin was measured by radioimmunoassay. Pulses of oxytocin were analyzed using the computerized Pulsar pulse detection algorithm. A pulsatile pattern of oxytocin concentrations was found in the CSF of lactating and nonlactating monkeys. The ultradian pulses of oxytocin were superimposed upon the diurnal rhythm of oxytocin in CSF. We conclude that frequent sampling of CSF provides a way to monitor moment-to-moment changes in central nervous system concentrations of oxytocin in primates.
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PMID:Pulses of oxytocin in the cerebrospinal fluid of rhesus monkeys. 129 76

Two populations of oxytocin-staining neurons have been identified in the paraventricular nucleus: magnocellular neurons that terminate in the posterior pituitary and parvocellular neurons that terminate elsewhere in the central nervous system. Whether these oxytocin neurons are functionally separate was tested by measuring oxytocin concentrations in samples of peripheral blood and cerebrospinal fluid (CSF) obtained simultaneously from lactating rhesus monkeys during suckling. Lactating animals bearing temporary subarachnoid and venous catheters were maintained in a constant photoperiod (0600-1800 h). Samples of CSF were continuously withdrawn by peristaltic pump (0.1 mL/15 min) for 2-4 consecutive days from subarachnoid catheters with the tips placed at the T12-L1 level of the spinal column in four lactating monkeys 4 months postpartum and again after weaning. On 2 of these days, we observed and recorded periods of infant suckling and collected peripheral blood samples (1.2 mL) from the mother at 5-min intervals for 60 min. Oxytocin was measured in blood and CSF by RIA. Oxytocin concentrations increased in the plasma of the lactating monkeys during periods of nursing, with peak concentrations ranging from 4-16.7 microU/mL. No increase in plasma oxytocin was found on the day after the infant was weaned. Variations in the concentrations of oxytocin in CSF were independent of the suckling stimulus and plasma oxytocin concentrations and occurred during observed periods of no nipple contact by the infant and at the time of weaning after the infant had been removed from the mother. Each lactating animal also displayed a normal circadian variation in CSF oxytocin concentrations, with peak and nadir levels during light and dark hours, respectively. We conclude that release of oxytocin into the CSF of lactating monkeys is disassociated from release into the peripheral circulation. The data further support the conclusion that neuronal pathways giving rise to oxytocin in the CSF and the periphery are anatomically and functionally separate in primates.
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PMID:Pattern of oxytocin concentrations in the plasma and cerebrospinal fluid of lactating rhesus monkeys (Macaca mulatta): evidence for functionally independent oxytocinergic pathways in primates. 222 10

The biosynthesis of oxytocin, vasopressin and their associated neurophysins were studied in the projection from the paraventricular nucleus of the hypothalamus to the spinal cord in individual freely-moving adult male rats. Neuropeptide biosynthesis was studied in vivo by the delivery of [35S]cysteine through stereotaxically implanted indwelling cannulae using an osmotic minipump delivery system. Following the appropriate chase times, the neural lobe and spinal cord segments T1-T4 and T12-L2 were removed from fresh tissue; in addition, the nucleus of the solitary tract was punched from frozen coronal sections. The radiolabeled peptides were purified from the tissue homogenates by sequential linear and exponential gradient elution from reverse-phase high performance liquid chromatography columns. This approach has allowed us to purify radiolabeled oxytocin and vasopressin from both the upper and lower spinal cord. However, the kinetics of oxytocin and vasopressin biosynthesis appeared to be remarkably different, as judged by their differential labeling with different pulse and chase times. Additionally, the use of different chase periods following the pulse of radiolabel has allowed us to determine that oxytocin reaches the spinal cord via the fast component of axonal transport (greater than 8 mm h-1). Using immunoprecipitation and purification by high performance liquid chromatography, we were also able to purify radiolabeled neurophysins from spinal cord tissue homogenates. These results lend further support to a role for oxytocin and vasopressin in the modulation of autonomic nervous system function and to the role of the paraventricular nucleus as an integration center for endocrine and autonomic function.
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PMID:In vivo biosynthesis and transport of oxytocin, vasopressin and neurophysin from the hypothalamus to the spinal cord. 242 Nov 98

Oxytocin and vasopressin (AVP) were previously reported to have a diurnal rhythm in cerebrospinal fluid (CSF) collected from the cervical cistern of chaired, intact male rhesus monkeys. In the present study, we continuously sampled CSF from temporary indwelling catheters placed in the spinal subarachnoid space of unanesthetized monkeys maintained on tether and swivel systems. CSF was collected from intact and castrate female rhesus monkeys and intact female and castrate, adrenalectomized male cynomolgus monkeys to determine if oxytocin and AVP rhythms are expressed in spinal subarachnoid CSF, if the magnitude of the CSF rhythm displays a rostral-caudal gradient, and if the rhythm is present in adrenalectomized and castrate monkeys, or is specific to the sex or species of macaque. Monkeys, maintained on a 12-hour light/dark cycle with lights on from 06.00 to 18.00 h, had 19-gauge epidural catheters introduced at the L4-L5 intervertebral space and advanced cephalad in the subarachnoid space. The proximal end of the catheter was connected to a peristaltic pump for continuous removal of CSF (0.5 ml/h) and hourly CSF samples were radioimmunoassayed for oxytocin and AVP. For rostral-caudal studies, the distal tip of the catheter was repositioned every few days to collect CSF from 3 levels of the spinal subarachnoid space: C5-6, T5-6, T12-L1. Each animal had a diurnal CSF oxytocin rhythm with peak and trough oxytocin levels during early light and dark periods, respectively. The magnitude of the oxytocin rhythm differed among animals, but was consistent in an animal from day to day.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Circadian rhythm of oxytocin in the cerebrospinal fluid of rhesus and cynomolgus monkeys: effects of castration and adrenalectomy and presence of a caudal-rostral gradient. 251 62

Intramammary pressure was recorded in anaesthetized lactating rats during electrical stimulation of the anterolateral pathways in the T12/L1 region of the spinal cord. In 18 rats, electrical stimulation at 10 Hz or more for 10-30 s caused a reproducible increase in intramammary pressure. The mammary gland responses were similar to those resulting from stimulation of the neurohypophysis with the same parameters, and were eliminated after complete destruction of the neural stalk; they were not associated with any consistent change in blood pressure. In 3 rats, a mammary gland response to spinal cord stimulation was obtained only after administration of the beta-adrenergic blocker, propranolol, which facilitates suckling-induced reflex milk-ejections. These results suggest that spinal cord stimulation can cause the release of oxytocin; the functional significance of such a release is discussed in relation to the milk-ejection reflex.
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PMID:Reproducible increases in intramammary pressure after spinal cord stimulation in lactating rats. 608 76

The preganglionic sympathetic neurons in the intermediolateral cell column of the thoracic and upper lumbar segments of the spinal cord which innervate the chromaffin cells in the adrenal medulla, sympathoadrenal preganglionic neurons, were identified by the method of retrograde axonal transport of the fluorescent dyes Fast Blue and True Blue. In rats, Fast Blue or True Blue was injected into the medulla of the left adrenal gland. After a survival period of 5 days, the animals were perfusion fixed, the thoracic and lumbar spinal cord sectioned and processed for the immunofluorescent localization of met-enkephalin, neurophysin, oxytocin, serotonin, somatostatin and substance P immunoreactivity. Neuronal perikarya which were retrogradedly-labeled with Fast Blue or True Blue were observed in the intermediolateral cell column from the T1 to the L2 spinal cord segments. The distribution of the sympathoadrenal neurons was determined by counting the number of retrogradedly-labeled neurons per spinal cord segment. In the five animals used for quantifying the sympathoadrenal preganglionic neurons, the majority (72.3%) of the retrogradely-labeled neurons counted per spinal cord were located within the T7-T12 segments. The T9 segment contained the largest average number (20.1%) of retrogradely-labeled cells in a single segment. Met-enkephalin, serotonin and substance P immunoreactive fibers were prominent in the intermediolateral cell column, whereas oxytocin, neurophysin and somatostatin immunoreactive fibers were sparse. The met-enkephalin, serotonin and substance P fibers were seen surrounding both unlabeled and retrogradely-labeled neurons; somatostatin fibers appeared to preferentially contact retrogradely-labeled neurons; whereas, the neurophysin and oxytocin fibers were not found in proximity to retrogradely-labeled neurons. Met-enkephalin, neurophysin, oxytocin, somatostatin and substance P immunoreactivity were depleted in the intermediolateral cell column below the level of a spinal cord transection. Serotonin immunoreactivity was depleted in the intermediolateral cell column below the level of the transection for five to six segments, but sparse networks of immunoreactive fibers were observed in both the intermediolateral cell column and the ventral horn in more caudal segments. Met-enkephalin, serotonin, somatostatin and substance P immunoreactivity were decreased in both the contralateral and ipsilateral intermediolateral cell column below the level of a spinal cord hemisection, suggesting that both crossed and uncrossed descending pathways exist. Neurophysin and oxytocin immunoreactivity were depleted below the level of the hemisection in the ipsilateral intermediolateral cell column without noticeable decrease in the level of immunoreactivity in the contralateral intermediolateral cell column, suggesting that a decussation does not occur at the level of the spinal cord, but may exist above the level of the hemisection...
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PMID:The differential distribution and relationship of serotoninergic and peptidergic fibers to sympathoadrenal neurons in the intermediolateral cell column of the rat: a combined retrograde axonal transport and immunofluorescence study. 618 Mar 52

Oxytocin binding sites were detected by autoradiography on films and emulsion-coated sections in the spinal cord of adult and postnatal rats from C8 to L2, using a highly selective 125I-labelled oxytocin antagonist. Oxytocin binding sites were detected on all transverse sections in the dorsal horn, where labelling was scattered over laminae I and II. The autonomic areas, i.e. the intermediolateral cell column, the central grey (lamina X) and the nucleus intercalatus were labelled. Binding in the intermediolateral cell column was most frequently observed on sections from T9 to T11 in adult and T7 to T8 in postnatal rats. In this location, oxytocin binding sites were highly concentrated on cell bodies of putative sympathetic preganglionic neurons; however, not all of these cells were labelled. Diffuse labelling occurred on the dorsal part of the central grey, mainly between T8 and L2. Isolated labelled cells belonging to the nucleus intercalatus were scattered between the central canal and the intermediolateral cell column. In addition, oxytocin binding sites were found on some motoneurons of the lateral group of T12-T13, but only in postnatal rats. The distribution of oxytocin binding sites in the rat spinal cord coincides with that of the oxytocin innervation and strongly suggests a modulatory role of this peptide in sensory and autonomic functions.
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PMID:Localization of oxytocin binding sites in the thoracic and upper lumbar spinal cord of the adult and postnatal rat: a histoautoradiographic study. 813 Sep 36

A 30-year-old pregnant woman (151 cm, 49 kg) with twin gestation who had got pregnant with frozen-thawed embryo transfer was scheduled to undergo cesarean section at 37 weeks of gestation. Combined spinal and epidural anesthesia was performed separately at the T12-L1 (epidural) and at the L3-4 interspace (spinal). The sensory anesthesia was extended to T2 and the operation was started. The cesarean delivery was uneventful and healthy 2,370 g and 2,334 g neonates were delivered. Five minutes after the delivery, placenta was removed manually from the uterus. Despite using oxytocin, methylergometrine and prostaglandin F2alpha, uterine contraction was severely impaired and massive bleeding occurred. General anesthesia was not commenced and packed red blood cells, fresh frozen plasma and cryoprecipitate were given. Uterus gradually contracted and the patient was transferred to the ward. However, massive bleeding continued postoperatively, and magnetic resonance imaging indicated retained placenta. Total hysterectomy was performed on the second postoperative day. Atonic bleeding and placental invasion should be the main causes of massive bleeding. Frozen-thawed embryo transfer might be one of the important factors for placental invasion. We have to prepare for massive bleeding during and after the cesarean section in patients receiving frozen-thawed embryo transfer.
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PMID:[Massive bleeding during and after cesarean section in a patient receiving frozen-thawed embryo transfer]. 2336 80