Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P01185 (vasopressin)
23,126 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Hormonal, mean arterial blood pressure, forearm blood flow and heart rate responses to graded dopamine infusion (0.5-2.0 micrograms/kg/min) were examined in 10 men with untreated essential hypertension WHO group I (147 +/- 4/100 +/- 1 mmHg, means +/- SE), and in 10 normotensive men (129 +/- 2/85 +/- 1 mmHg), all 40 years old. Another 12 normotensive men (126 +/- 3/80 +/- 2 mmHg) were given only saline infusion. Dopamine increased heart rate significantly in the hypertensive group (8 +/- 2 beats/min, p less than 0.001), but the heart rate remained unchanged in the normotensive group (1 +/- 1 beats/min, NS). Although dopamine infusion tended to decrease mean blood pressure, the changes were not significantly different from those observed in the control group. No change in forearm blood flow was observed in either group. In the groups given dopamine, prolactin levels decreased only slightly compared to the control group given saline, the decrement tending to be more pronounced in the hypertensive group. Plasma vasopressin remained unchanged in both groups during dopamine infusion. These results indicate that hypertensive patients exhibit increased sensitivity to the cardiovascular effects of dopamine.
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PMID:Endocrine and haemodynamic responses to graded dopamine infusion in essential hypertension. 360 15

In order to confirm whether dopamine inhibits the antidiuretic action of vasopressin in mammalian kidney, we examined interactions among arginine vasopressin (AVP), dopamine and haloperidol in water-loaded ethanol anesthetized rats. The submaximal dose of AVP causing antidiuresis was 80 microU in this preparation. Dopamine at the doses of 0.11, 1.1 and 11 micrograms/100 g body weight (i.v.) inhibited the antidiuretic effect of 80 microU AVP by 18 +/- 7, 27 +/- 6 and 36 +/- 14%, respectively. The effect of 1.1 micrograms/100 g body weight dopamine in inhibiting the action of AVP was completely reversed by haloperidol at 2.3 micrograms/100 g body weight. Single administration of dopamine or haloperidol was without effect on urine flow. These observations support the view that dopamine inhibits the antidiuretic action of vasopressin by dopaminergic receptors also in the mammalian kidney.
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PMID:Dopaminergic modulation of the renal effect of arginine-vasopressin in water-loaded rats. 402 Dec 28

The effect of intracerebroventricular (I.C.V.) micro-injections of dopamine on vasopressin (AVP) release was investigated in normally hydrated and hydrated rats anaesthetized with urethane, hormone concentrations being determined by radioimmunoassay. Dopamine given in doses of less than 25 micrograms had little effect on AVP concentrations already elevated as a result of anaesthesia and surgery. Doses of over 25 micrograms produced a transient increase in AVP concentrations followed by a fall. Both the increase and the fall were statistically significant. Pimozide (400 micrograms/kg) blocked the fall in AVP concentrations following dopamine. A fall was still seen after the administration of haloperidol (400 micrograms/kg) but it was only significant 20 min after the injection of dopamine. The changes in AVP concentration after the administration of naloxone (400 micrograms/kg) were not statistically significant. In water-loaded rats I.C.V. micro-injections of dopamine produced a dose-dependent antidiuresis over the range 1-25 micrograms. An injection of 25 micrograms dopamine in these animals produced an increase in AVP concentrations to 1.8 +/- 0.51 microunits/ml and a fall in urine flow which could be approximately matched by an infusion of vasopressin of 15 microunits/min. The antidiuresis in response to dopamine could be blocked by haloperidol. The response to dopamine in the anaesthetized animals depends on a number of factors including the initial activity of the neurohypophysial system.
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PMID:Central effects of dopamine on vasopressin release in the normally hydrated and water-loaded rat. 669 83

1. In a preliminary study, a positive pressure of 25 mmHg applied to the lower body raised right atrial pressure by a mean of 7 mmHg. 2. Sustained application of lower-body positive pressure (LBPP) in six normal adult males increased sodium excretion ([Na]V) from a control level of 126.5 +/- 10 mumol/min to 213 +/- 21 mumol/min (P = 0.003) and fractional sodium excretion (EfNa) from 0.7 +/- 0.1 to 1.2 +/- 0.1 (P = 0.001). 3. Urine flow (UF) increased from 0.85 +/- 0.07 ml/min to 4.1 +/- 0.8 ml/min (P = 0.002), osmolar clearance (Cosm) from 2.6 +/- 0.13 ml/min to 4.2 +/- 0.4 ml/min (P = 0.003) and free water clearance (CH2O) from -1.75 +/- 0.1 ml/min to -0.1 +/- 0.01 ml/min (P = 0.001). Creatinine clearance (Ccr) showed no significant change. 4. After dopamine blockade with domperidone, LBPP did not cause a rise in [Na]V or EfNa. However, urine flow, Cosm. and CH2O remained significantly above control values, implying persistent suppression of antidiuretic hormone. 5. Dopamine blockade without positive pressure did not affect basal sodium excretion.
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PMID:Abolition, by dopamine blockade, of the natriuretic response produced by lower-body positive pressure. 710 30

Norepinephrine and epinephrine concentrations in the caudal and rostral part of the nucleus tractus solitarii (NTS) and in locus coeruleus (LC) of Sabra hypertension prone (SBH) rats are 2-4-fold higher than in the parent Sabra (SB) strain; SB rats have higher concentrations than the Sabra hypertension resistant (SBN) rats. Dopamine concentrations were higher in SBH as compared to SB and SBN rats only in the caudal NTS. Vasopressin concentrations in the NTS of SBH were 3-fold higher than the levels found in SB or SBN rats. These data suggest that catecholamines and vasopressin in specific brainstem nuclei are involved in either the pathogenesis or central response to hypertension in SBH rats.
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PMID:Catecholamines and vasopressin in hindbrain nuclei of hypertension prone and resistant rats. 717 1

Catecholamine and vasopressin content were studied in discrete brain nuclei of the Sabra strain of hypertension prone (SBH) and resistant (SBN) rats. Higher concentrations of dopamine, norepinephrine and epinephrine were observed in the median eminence of SBN compared to SBH or controls (SB) rats. Dopamine and epinephrine levels were higher in the lateral septal nucleus of SBH rats as compared to SBN or SB. Vasopressin content in discrete regions along the hypothalamo-pituitary axis was elevated in both SBH and SBN as compared to SB, but were especially elevated in the SBH group. The catecholamine and vasopressin changes found in SBH are different than those described in other genetically hypertensive rats indicating a difference in either the pathogenesis or central response to hypertension of this strain.
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PMID:Catecholamines and vasopressin in forebrain nuclei of hypertension prone and resistant rats. 732 83

A study was performed to investigate the neurohypophyseal dopaminergic axis in terms of its biosynthetic activity and possible changes associated with spontaneous hypertension (SHR). An in vitro system was used in which isolated neuro-intermediate lobes were incubated with the catecholamine precursor, 3H-tyrosine. Dopamine (DA) content and 3H-DA were monitored using electrochemical detection coupled with high pressure liquid chromatographic separation. A time course study showed that there was significant incorporation of 3H-tyrosine into 3H-DA. In the SHR, both neurohypophyseal DA content and biosynthetic activity were reduced. Tissue levels of 3H-DA decreased from 651 to 297 dpm/posterior pituitary. A test of the effect of dehydration on neurohypophyseal dopaminergic activity revealed that water deprivation (48 hrs) caused an increase in DA biosynthesis in the hypertensive, but not the normotensive animal. This may have been due to a greater stimulation of the neurohypophyseal axis in the SHR since these animals showed significantly higher plasma vasopressin levels and hematocrits in response to dehydration. These results demonstrate that the neurohypophysis contains an active dopaminergic system which is altered in genetic hypertension.
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PMID:Neurohypophyseal dopamine biosynthesis in the spontaneously hypertensive rat. 733 97

The effect of dopamine on the arterioles (50.8-95.2 microns) in the cremaster muscle was examined to determine its effect on microcirculation. Anesthetized rats were used under a light microscope connected to a videocamera. Drugs were applied using small round filter paper (370 microns in diameter) containing the drug and placed in the immediate vicinity of the arteriole on the cremaster with a micromanipulator. The dose of the drug applied was represented by concentration of the drug solution in which the filter paper was immersed. Dopamine (10(-6)-10(-4)M) induced neither constriction nor dilation of the arteriole in the cremaster. Papaverine (10(-2)M) did not dilate the arteriole. However, the arterioles were constricted by noradrenaline (10(-6)-10(-4)M) and vasopressin (10(-7)M) in a dose-dependent manner. Noradrenaline (10(-4)M)-induced constriction was blocked by concomitant application of dopamine (10(-4)M). This effect of dopamine was antagonized by SCH23390 (10(-3)M). However, isoproterenol (10(-3)M) did not affect the arteriole, nor inhibit noradrenaline (10(-4)M)-induced constriction of the arterioles. While forskolin (10(-2)M) alone did not produce constriction or dilation of the arterioles, it inhibited noradrenaline (10(-4)M)-induced constriction of the arteriole. These results suggest that dopamine prevents the constriction of the arteriole induced by noradrenaline, by activation of DA1 receptors, which activates adenylate cyclase.
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PMID:Inhibitory effects of dopamine on noradrenaline-induced constriction of arterioles in vivo in the striated cremaster muscle. 848 19

We have reported previously that regions encompassing the cerebral ventricle may contain dopamine receptors responsible for facilitatory roles in the osmotic release of vasopressin in conscious rats. In order to explore the location of these receptors, we injected (0.5 mul) the dopamine antagonist haloperidol (13.3 nmol) or dopamine (26.4 nmol) topically into the anteroventral third ventricular region or the paraventricular nucleus of rats, and their effects on the levels of plasma vasopressin and its controlling factors were examined in the presence or absence of an osmotic stimulus. The effects of haloperidol injections into the ventral tegmental area were also tested to study whether information associated with drinking behavior may affect the osmotic vasopressin secretion. Intravenous infusion (0.1 ml kg-1 body wt min-1) of hypertonic saline (2.5 mol/l) enhanced plasma vasopressin 15 and 30 min later, and this was accompanied by an augmentation of plasma osmolality, sodium and chloride, and by elevated or unaltered arterial pressure. The vasopressin response was abolished by haloperidol injection into the anteroventral third ventricular region 10 min before the beginning of the hypertonic saline infusion. The injection sites were confirmed histologically to have been in or near the organum vasculosum of the laminae terminalis and a ventral part of the median preoptic nucleus. Similarly, a partial but significant reduction of the vasopressin response was noted after bilateral injections of haloperidol into the ventral tegmental area, whereas bilateral haloperidol injections into the paraventricular nucleus had no appreciable effect. The responses of plasma osmolality, electrolytes and arterial pressure to the osmotic load were not affected significantly by haloperidol injections into the anteroventral third ventricular region, ventral tegmental area or the paraventricular nucleus. The iv infusion of isotonic saline (0.15 mol/l) did not change plasma vasopressin and the other variables significantly, and this was also the case when preceded by application of haloperidol into the anteroventral third ventricular region, ventral tegmental area or the paraventricular nucleus. Dopamine injection into the anteroventral third ventricular region increased plasma vasopressin 5 min later, without affecting plasma osmolality, electrolytes or arterial pressure. On the basis of these results, we concluded that dopamine receptors responsible for facilitatory roles in osmotically stimulated vasopressin secretion may exist in the anteroventral third ventricular region and ventral tegmental area.
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PMID:Possible contribution of dopaminergic receptors in the anteroventral third ventricular region to hyperosmolality-induced vasopressin secretion in conscious rats. 863 May 27

Oxytocin (OT) release within the brain is thought to play a major role in inducing maternal behaviour in a number of mammalian species but little is known about the sites of release which are important in this respect. We have investigated whether the paraventricular nucleus of the hypothalamus (PVN) is a site of OT action on maternal behaviour in the sheep. In vivo microdialysis and retrodialysis was used to determine whether OT is released in the region of the PVN during the post-partum induction of maternal behaviour and if its release at this site can stimulate maternal behaviour in non-pregnant animals. In vivo sampling showed that OT concentrations increased significantly in the region of PVN at birth. When OT was retrodialysed bilaterally into the PVN (1 or 10 microM) of multiparous ewes treated with progesterone and oestradiol to stimulate lactation, maternal behaviour was induced in a significant number of animals (1 microM, 6/8 and 10 microM, 5/8) compared with controls (0/8 ewes). Similar infusions of the ring structure of OT, tocinoic acid (TOC-10 microM), also induced maternal behaviour in a significant proportion of animals (5/6 ewes) as did intracerebroventricular (ICV) OT (6/8 ewes) and artificial stimulation of the vagina and cervix (VCS, 8/9 ewes). On the other hand, vasopressin (AVP) 1 microM did not induce maternal behaviour in any ewes and a 10 microM dose only induced it in 2/8 animals. The neurochemical changes accompanying the above treatments were also investigated. Noradrenaline concentrations increased in the PVN after the retrodialysis administration of OT 1 microM and 10 microM, TOC 10 microM and AVP 1 microM, OT ICV and VCS. Dopamine concentrations were also increased by OT 10 microM, TOC 10 microM, AVP 1microM and OT ICV. Aspartate and glutamate concentrations were significantly reduced by retrodialysis infusions of OT 1 microM and AVP 1 and 10 microM but not by any other treatment. Finally, the retrodialysis infusion of OT and TOC, as well as ICV OT, significantly increased plasma OT release whereas AVP infusions did not. These results provide evidence that OT is released in the PVN during parturition and is important for the induction of maternal behaviour. It seems probable that OT release at this site has a positive feedback effect on both parvocellular and magnocellular OT neurons to facilitate co-ordinated OT release both in central OT terminal regions (to facilitate maternal behaviour) and peripherally into the blood (to facilitate uterine contractions/milk let down). The potential functional roles for the actions of OT on monoamine and amino acid transmitter release in the PVN are discussed.
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PMID:The role of oxytocin release in the paraventricular nucleus in the control of maternal behaviour in the sheep. 873 Jun 50


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