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1.
Actual. osteol ; 16(2): [132]-[140], mayo.-ago. 2020. ilus
Article in Spanish | LILACS | ID: biblio-1129806

ABSTRACT

La oxitocina (OXT) como la arginina-vasopresina (AVP) son dos hormonas primitivas secretadas por la hipófisis posterior. Sus receptores están mucho más ampliamente distribuidos en el organismo de lo que se pensaba originalmente, incluido el hueso. En los estudios preclínicos, la OXT ha mostrado ser anabólica para el hueso, promoviendo la osteogénesis sobre la adipogénesis y favoreciendo la actividad osteoblástica sobre la osteoclástica. Tanto los osteoblastos como los osteoclastos tienen receptores para la OXT, y los efectos de los estrógenos sobre la masa ósea en ratones está mediada por lo menos en parte por la OXT. El mecanismo preciso por el cual la activación de los receptores de oxitocina (OXTR) se traduce en un incremento de la formación ósea permanece poco claro. La AVP también podría afectar el esqueleto en forma directa. Dos de los receptores de la AVP, V1a y V2 están expresados en osteoblastos y osteoclastos. La inyección de AVP en ratones de tipo salvaje aumenta la formación osteoclastos que producen resorción y reduce los osteoblastos formadores de hueso. En forma opuesta, la exposición de precursores osteoblásticos a antagonistas de los receptores V1a o V2, incrementan la osteoblastogénesis, como también lo hace la deleción genética del receptor V1a. (AU)


Both oxytocin (OXT) and argininevasopressin (AVP) are primitive hormones secreted by the posterior pituitary gland. OXT receptors are much more widely distributed in the body than originally thought, including in bone. In preclinical studies, OXT has been shown to be anabolic for bone, promoting osteogenesis over adipogenesis and favoring osteoblastic over osteoclastic activity. Both osteoblasts and osteoclasts have receptors for OXT, and the effects of estrogen on bone mass in mice is mediated at least in part by OXT. The precise mechanism by which the activation of oxytocin receptors (OXTRs) results in an increase in bone formation remains unclear. AVP could also have direct actions on the skeleton. The two AVP receptors, V1a and V2, are expressed in osteoblasts and osteoclasts. Injection of AVP in wild-type mice increases the formation of osteoclasts increasing bone resorption, and reduces bone-forming osteoblasts. On the contrary, the exposure of osteoblastic precursors to V1a and V2 antagonists increase osteoblastogenesis, the same as the genetic deletion of the V1a receptor. (AU)


Subject(s)
Humans , Animals , Mice , Pituitary Hormones, Posterior/biosynthesis , Arginine Vasopressin/adverse effects , Oxytocin/therapeutic use , Osteoblasts/physiology , Osteoclasts/physiology , Osteogenesis , Osteoporosis/therapy , Pituitary Hormones, Posterior/physiology , Arginine Vasopressin/antagonists & inhibitors , Arginine Vasopressin/biosynthesis , Arginine Vasopressin/physiology , Arginine Vasopressin/therapeutic use , Oxytocin/biosynthesis , Oxytocin/adverse effects , Oxytocin/physiology , Signal Transduction , Bone Density , Bone Density/drug effects , Receptors, Oxytocin/biosynthesis , Receptors, Oxytocin/physiology , Estradiol/therapeutic use , Estrogens/physiology
3.
Article in English | WPRIM | ID: wpr-758995

ABSTRACT

The kidney collecting duct (CD) is a tubular segment of the kidney where the osmolality and final flow rate of urine are established, enabling urine concentration and body water homeostasis. Water reabsorption in the CD depends on the action of arginine vasopressin (AVP) and a transepithelial osmotic gradient between the luminal fluid and surrounding interstitium. AVP induces transcellular water reabsorption across CD principal cells through associated signaling pathways after binding to arginine vasopressin receptor 2 (AVPR2). This signaling cascade regulates the water channel protein aquaporin-2 (AQP2). AQP2 is exclusively localized in kidney connecting tubules and CDs. Specifically, AVP stimulates the intracellular translocation of AQP2-containing vesicles to the apical plasma membrane, increasing the osmotic water permeability of CD cells. Moreover, AVP induces transcription of the Aqp2 gene, increasing AQP2 protein abundance. This review provides new insights into the transcriptional regulation of the Aqp2 gene in the kidney CD with an overview of AVP and AQP2. It summarizes current therapeutic approaches for X-linked nephrogenic diabetes insipidus caused by AVPR2 gene mutations.


Subject(s)
Aquaporin 2 , Arginine Vasopressin , Body Water , Cell Membrane , Diabetes Insipidus, Nephrogenic , Gene Expression Regulation , Homeostasis , Kidney , Kidney Tubules, Collecting , Osmolar Concentration , Permeability , Phenobarbital , Receptors, Vasopressin , Water
4.
Article in English | WPRIM | ID: wpr-763150

ABSTRACT

PURPOSE: Control of metastatic spread of colorectal cancer (CRC) remains as a major therapeutic challenge. [V4 Q5 ]dDAVP is a vasopressin peptide analog with previously reported anticancer activity against carcinoma tumors. By acting as a selective agonist of arginine vasopressin type 2 membrane receptor (AVPR2) present in endothelial and tumor cells, [V⁴Q⁵]dDAVP is able to impair tumor aggressiveness and distant spread. Our aim was to evaluate the potential therapeutic benefits of [V⁴Q⁵]dDAVP on highly aggressive CRC disease using experimental models with translational relevance. MATERIALS AND METHODS: Murine CT-26 and human Colo-205 AVPR2-expressing CRC cell lines were used to test the preclinical efficacy of [V⁴Q⁵]dDAVP, both in vitro and in vivo. RESULTS: In syngeneic mice surgically implanted with CT-26 cells in the spleen, sustained intravenous treatment with [V⁴Q⁵]dDAVP (0.3 µg/kg) dramatically impaired metastatic progression to liver without overt signs of toxicity, and also reduced experimental lung colonization. The compound inhibited in vivo angiogenesis driven by Colo-205 cells in athymic mice, as well as in vitro endothelial cell migration and capillary tube formation. [V⁴Q⁵]dDAVP exerted AVPR2-dependent cytostatic activity in vitro (IC₅₀ 1.08 µM) and addition to 5-fluorouracil resulted in synergistic antiproliferative effects both in CT-26 and Colo-205 cells. CONCLUSION: The present preclinical study establishes for the first time the efficacy of [V⁴Q⁵]dDAVP on CRC. These encouraging results suggest that the novel second generation vasopressin analog could be used for the management of aggressive CRC as an adjuvant agent during surgery or to complement standard chemotherapy, limiting tumor angiogenesis and metastasis and thus protecting the patient from CRC recurrence.


Subject(s)
Animals , Arginine Vasopressin , Capillaries , Cell Line , Colon , Colorectal Neoplasms , Complement System Proteins , Drug Therapy , Endothelial Cells , Fluorouracil , Humans , In Vitro Techniques , Liver , Lung , Membranes , Mice , Mice, Nude , Models, Theoretical , Neoplasm Metastasis , Recurrence , Robenidine , Spleen , Vasopressins
5.
Article in Chinese | WPRIM | ID: wpr-773483

ABSTRACT

OBJECTIVE@#To investigate the mechanism by which doublecortin promotes the recovery of cytoskeleton in arginine vasopressin (AVP) neurons in rats with electrical lesions of the pituitary stalk (PEL).@*METHODS@#Thirty-two SD rats were randomized into PEL group with electrical lesions of the pituitary stalk through the floor of the skull base (=25) and sham operation group (=7), and the daily water consumption (DWC), daily urine volume (DUV) and urine specific gravity (USG) of the rats were recorded. Four rats on day 1 and 7 rats on each of days 3, 7 and 14 after PEL as well as the sham-operated rats were sacrificed for detection of the expressions of β-Tubulin (Tuj1), doublecortin and caspase- 3 in the AVP neurons of the supraoptic nucleus using immunofluorescence assay and Western blotting.@*RESULTS@#After PEL, the rats exhibited a typical triphasic pattern of diabetes insipidus, with the postoperative days 1-2 as the phase one, days 3-5 as the phase two, and days 6-14 as the phase three. Immunofluorescent results indicated the repair of the AVP neurons evidenced by significantly increased doublecortin expressions in the AVP neurons following PEL; similarly, the expression of Tuj1 also increased progressively after PEL, reaching the peak level on day 7 after PEL. The apoptotic rates of the AVP neurons exhibited a reverse pattern of variation, peaking on postoperative day 3 followed by progressive reduction till day 14. Western blotting showed that the expressions of c-Jun and p-c-Jun were up-regulated significantly on day 3 ( < 0.05) and 7 ( < 0.01) after PEL, while an upregulated p-JNK expression was detected only on day 3 ( < 0.05), as was consistent with the time-courses of neuronal recovery and apoptosis after PEL.@*CONCLUSIONS@#JNK/c-Jun pathway is activated after PEL to induce apoptosis of AVP neurons in the acute phase and to promote the repair of neuronal cytoskeleton by up-regulation of doublecortin and Tuj1 expressions.


Subject(s)
Animals , Apoptosis , Arginine Vasopressin , Pharmacology , Cytoskeleton , Metabolism , MAP Kinase Signaling System , Neurons , Cell Biology , Pituitary Gland , Cell Biology , Wounds and Injuries , Proto-Oncogene Proteins c-jun , Metabolism , Random Allocation , Rats , Rats, Sprague-Dawley , Regeneration , Tubulin , Metabolism
6.
Article in English | WPRIM | ID: wpr-158001

ABSTRACT

Anesthetic experience in frontotemporal dementia (FTD) with severe hypotension associated autonomic dysfunction has not yet been reported. Here in case, we report on the case of treatment with vasopressin to refractory hypotension in FTD patient. A 54-year-old male presented with a ten-year history of FTD with frequent syncope. The patient was scheduled to undergo subtotal gastrectomy for resection of stomach cancer. During the operation, sudden hypotension occurred and it was refractory to fluid and 1 unit of blood resuscitation and did not respond to catecholamine. Transesophageal echocardiography showed normal heart with adequate volume state. After intravenous administration of arginine vasopressin, the patient's vital signs returned to baseline values. Arginine vasopressin might be considered as a valuable alternative for treatment of severe refractory hypotension in autonomic dysfunction patients with FTD.


Subject(s)
Administration, Intravenous , Arginine Vasopressin , Echocardiography, Transesophageal , Frontotemporal Dementia , Gastrectomy , Heart , Humans , Hypotension , Male , Middle Aged , Resuscitation , Stomach Neoplasms , Syncope , Vasopressins , Vital Signs
7.
Article in English | WPRIM | ID: wpr-120968

ABSTRACT

Arginine vasopressin (AVP), also known as antidiuretic hormone, is a peptide endogenously secreted by the posterior pituitary in response to hyperosmolar plasma or systemic hypoperfusion states. When administered intravenously, it causes an intense peripheral vasoconstriction through stimulation of V₁ receptors on the vascular smooth muscle. Patients in refractory shock associated with severe sepsis, cardiogenic or vasodilatory shock, or cardiopulmonary bypass have inappropriately low plasma levels of AVP (‘relative vasopressin deficiency’) and supersensitivity to exogenously-administered AVP. Low doses of AVP and its synthetic analog terlipressin can restore vasomotor tone in conditions that are resistant to catecholamines, with preservation of renal blood flow and urine output. They are also useful in the treatment of refractory arterial hypotension in patients chronically treated with renin-angiotensin system inhibitors, cardiac arrest, or bleeding esophageal varices. In the perioperative setting, they represent attractive adjunct vasopressors in advanced shock states that are unresponsive to conventional therapeutic strategies.


Subject(s)
Arginine Vasopressin , Cardiopulmonary Bypass , Catecholamines , Esophageal and Gastric Varices , Heart Arrest , Hemorrhage , Humans , Hypotension , Muscle, Smooth, Vascular , Plasma , Renal Circulation , Renin-Angiotensin System , Sepsis , Shock , Shock, Hemorrhagic , Shock, Septic , Vasoconstriction , Vasopressins
8.
Article in Chinese | WPRIM | ID: wpr-286872

ABSTRACT

<p><b>OBJECTIVE</b>To study the distribution of single nucleotide polymorphisms (SNP) of arginine-vasopressin (AVP) gene rs66818855 and rs1078152 in Chinese Guangxi healthy population in comparison with that in different ethnic populations.</p><p><b>METHDOS</b>Polymerase chain reaction-single base extension (PCR-SBE) and DNA sequencing were used to detect the allele and genotype frequencies of AVP gene among 303 Chinese healthy individuals in Guangxi, China, and the results were compared with the reported frequencies in 4 other populations (HapMap-CEU, HapMap-YRI, HapMap-JPT, and HapMap-HCB) from Human Genome Project group (HapMap) data.</p><p><b>RESULTS</b>We found significant AVP gene polymorphisms in this Guangxi healthy population. The frequencies of allele and genotype of AVP gene rs66818855 and rs1078152 polymorphisms in this Guangxi population differed significantly from those in HapMap-CEU population (P<0.01), and allele frequencies of AVP gene rs66818855 polymorphism differed significantly from those in HapMap-YRI populations (P<0.05).</p><p><b>CONCLUSION</b>The distribution pattern of AVP gene polymorphisms in this Guangxi population is significantly different from that in other ethnic populations, which might account for the difference in the morbidity of AVP-related disease among different ethnic groups and may have important indications in the study of population genetics and anthropology.</p>


Subject(s)
Alleles , Arginine Vasopressin , Genetics , Asian Continental Ancestry Group , China , Gene Frequency , Genetics, Population , Genotype , Humans , Polymerase Chain Reaction , Polymorphism, Single Nucleotide
9.
Article in Chinese | WPRIM | ID: wpr-815133

ABSTRACT

To explore the influence of preventive use of vasopressin tannate on diabetes insipidus and serum sodium at the early postoperation of craniopharyngioma.
 Methods: The data of 83 patients, who underwent unilateral sub-frontal approach resection of craniopharyngioma between 2010 and 2014 by the same senior neurosurgeon, were retrospectively analyzed. The patients were divided into a vasopressin tannate group (used group) and a control group. The diabetes insipidus and serum sodium changes were compared between the two groups.
 Results: Compared with the control group, the incidence of diabetes insipidus decreased at the early postoperation in the vasopressin tannate group (P<0.05). There was high incidence of diabetes insipidus in patients with pituitary stalk excision and tumor close adhesion to the third ventricle floor at the early postoperation (P<0.05). Under such conditions, the incidence of diabetes insipidus in the vasopressin tannate group was decreased compared with the control group (P<0.05). Postoperative hypernatremia occurred in 37 patients (44.6%), and hyponatremia occurred in 60 patients (72.3%), the average time of the occurrence of hpernatremia and hyponatremia was 1.4 and 3.7 days after surgery. Postoperative high serum sodium and low serum sodium appeared alternately in 19 patients (22.9%). There was significant difference in the serum sodium distribution in the first day after surgery in both groups (P<0.05), and the percent of hpernatremia in the vasopressin tannate group was significantly less than that in the control group (P<0.05).
 Conclusion: Preventive use of vasopressin tannate can effectively reduce diabetes insipidus and hypernatremia incidence at the early postoperative stage after microsurgery for craniopharyngioma.


Subject(s)
Arginine Vasopressin , Therapeutic Uses , Craniopharyngioma , General Surgery , Diabetes Insipidus , Female , Humans , Hypernatremia , Epidemiology , Hyponatremia , Epidemiology , Incidence , Male , Microsurgery , Pituitary Gland , General Surgery , Pituitary Neoplasms , Postoperative Complications , Postoperative Period , Retrospective Studies
10.
Article in English | WPRIM | ID: wpr-97088

ABSTRACT

Appropriate control of diet and water intake is important for maintaining normal blood pressure, fluid and electrolyte homeostasis in the body. It is relatively understood that the amount of sodium and potassium intake directly affects blood pressure and regulates ion transporters; Na and K channel functions in the kidney. However, little is known about whether diet and water intake regulates Aquaporin (AQP) function. AQPs, a family of aquaporin proteins with different types being expressed in different tissues, are important for water absorption by the cell. Water reabsorption is a passive process driven by osmotic gradient and water permeability is critical for this process. In most of the nephron, however, water reabsorption is unregulated and coupled to solute reabsorption, such as AQP1 mediated water absorption in the proximal tubule. AQP2 is the only water channel founded so far that can be regulated by hormones in the kidney. AQP2 expressed in the apical membrane of the principal cells in the collecting tubule can be regulated by vasopressin (antidiuretic hormone) controlling the final volume of urine excretion. When vasopressin binds to its receptor on the collecting duct cells, it stimulates the translocation of AQP2 to the membrane, leading to increased water absorption via this AQP2 water channel. However, some studies also indicated that the AQP2 is also been regulated by vasopressin independent mechanism. This review is focused on the regulation of AQP2 by diet and the amount of water intake on salt and water homeostasis.


Subject(s)
Absorption , Aquaporin 2 , Arginine Vasopressin , Blood Pressure , Diet , Drinking , Homeostasis , Humans , Ion Transport , Kidney , Membranes , Nephrons , Osmolar Concentration , Permeability , Potassium , Sodium , Vasopressins , Water
11.
Article in English | WPRIM | ID: wpr-770888

ABSTRACT

BACKGROUND: Arginine vasopressin (AVP) is widely used as a vasopressor agent. Some recent studies have suggested that AVP may exert an immunomodulatory effect. However, the mechanism about the anti-inflammatory effect of AVP is not well known. We investigated the effect of AVP on the ihibitor of kappa B (IkappaBalpha)/nuclear factor-kappa B (NF-kappaB) pathway in RAW 264.7 cells. METHODS: Cultured RAW 264.7 cells were pretreated with AVP and stimulated with lipopolysaccharide (LPS). To evaluate the effect of AVP on inflammatory cytokines, the concentration of interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-alpha) were assessed by an enzyme-linked immunosorbent assay technique. The expression of IkappaBalpha and nuclear translocation of NF-kappaB p65 were measured by Western blotting, and IkappaB kinase (IKK) activity was analyzed by an in vitro immune complex kinase assay. To confirm the AVP effect on IkappaBalpha/NF-kappaB cascade and via V2 receptor, we added tolvaptan (V2 receptor antagonist) after AVP pretreatment. RESULTS: The increase of IL-6 and TNF-alpha in LPS-stimulated RAW 264.7 cells was suppressed by a treatment with AVP. Pretreatment of AVP inhibited increasing of IKK activity and IkappaBalpha degradation induced by LPS in RAW 264.7 cells. Furthermore, LPS induced and NF-kappaB transcription was inhibited by AVP pretreatment. The observed changes in IKK activity, IkappaBalpha degradation and NF-kappaB transcription by AVP was abolished by tolvaptan treatment. CONCLUSIONS: Our results suggest that AVP showed anti-inflammatory effect on LPS-induced IkappaBalpha/NF-kappaB cascade in mouse macrophages via V2 receptors.


Subject(s)
Animals , Antigen-Antibody Complex , Arginine Vasopressin , Blotting, Western , Cytokines , Enzyme-Linked Immunosorbent Assay , I-kappa B Kinase , Interleukin-6 , Macrophages , Mice , NF-kappa B , Phosphotransferases , Receptors, Vasopressin , Tumor Necrosis Factor-alpha
12.
Article in Chinese | WPRIM | ID: wpr-232563

ABSTRACT

<p><b>OBJECTIVE</b>To investigate the effect of arginine vasopressin (AVP) on alveolar fluid clearance (AFC) in acute lung injury (ALI).</p><p><b>METHODS</b>Forty-eight healthy adult Sprague-Dawley rats were randomly divided into control group, ALI model group and AVP treatment group. The pathological changes in the lungs, lung water content, alveolar permeability and AFC were observed, and the expressions of alveolar epithelial sodium channel (ENaC) and Na⁺, K⁺-ATPase were measured.</p><p><b>RESULTS</b>Compared with those in the model group, the rats treated with AVP showed significantly decreased alveolar permeability (0.27 ± 0.15 vs 0.59 ± 0.19) and lung water content (5.01 ± 1.59 vs 8.67 ± 1.79) (P<0.05) and increased AFC (23.56 ± 4.51 vs 8.28 ± 3.57) and of α-ENaC expressions (1.296 ± 0.322 vs 0.349 ± 0.141) and α1-Na⁺, K⁺-ATPase (1.421 ± 0.389 vs 0.338 ± 0.186) (P<0.05).</p><p><b>CONCLUSION</b>AVP can promote AFC in with ALI possibly by up-regulation of α-ENaC, α1-Na⁺, and K⁺-ATPase.</p>


Subject(s)
Acute Lung Injury , Drug Therapy , Animals , Arginine Vasopressin , Pharmacology , Epithelial Sodium Channels , Metabolism , Lung , Pathology , Pulmonary Alveoli , Rats , Rats, Sprague-Dawley , Sodium-Potassium-Exchanging ATPase , Metabolism
13.
Article in Chinese | WPRIM | ID: wpr-307710

ABSTRACT

<p><b>OBJECTIVE</b>To observe the clinical efficacy of acupuncture combined with auricular point sticking for menstrual headache and to discuss its mechanism.</p><p><b>METHODS</b>Eighty-five patients with menstrual headache were randomly divided into an observation group (43 cases) and a control group (42 cases). The observation group was treated with body acupuncture combined with auricular point sticking and the control group was treated with flunarizine hydrochloride capsules orally. The treatments of 3 menstrual cycles were required. The clinical efficacy was observed in the two groups. The content of serum prostaglandin F2α, (PGF2α) and plasma arginine vasopressin (AVP) in the menstrual periods of some patients randomly selected in the two groups was tested before and after treatment and was compared with that of 20 cases in a normal group. Results The total effective rate was 95.4% (41/43) in the observation group which was obviously superior to 81.0% (34/42) in the control group (P<0.01). Before treatment, the content of serum PGF2α and plasma AVP of patients in the two groups was higher than that in the normal group (all P<0.01). After treatment,the content of serum PGF2α and plasma AVP was lower than that before treatment in the two groups (P<0.01, P<0.05). The content of serum PGF2α in the observation group was decreased significantly compared with that in the control group (P<0.05) and returned to the level of the normal group.</p><p><b>CONCLUSION</b>Body acupuncture combined with auricular point sticking achieves positive efficacy for menstrual headache and its mechanism could be related to regulating the abnormal levels of serum PGF2α and plasma AVP.</p>


Subject(s)
Acupuncture Therapy , Acupuncture, Ear , Adolescent , Adult , Arginine Vasopressin , Blood , Dinoprost , Blood , Female , Headache , Blood , Therapeutics , Humans , Menstruation , Premenstrual Syndrome , Blood , Therapeutics , Treatment Outcome , Young Adult
14.
São Paulo; s.n; 2015. 131 p. tab, graf, ilus.
Thesis in Portuguese | LILACS | ID: biblio-972080

ABSTRACT

INTRODUÇÃO: A ressuscitação de baixo volume com solução salina hipertônica (SSH) ou terlipressina pode ser uma alternativa à administração de grandes volumes de cristaloides no tratamento do choque hemorrágico. O objetivo deste estudo foi avaliar os efeitos da HHS e terlipressina sobre a perfusão e oxigenação cerebral e investigar os mecanismos cerebrais envolvidos na microcirculação, função mitocondrial, atividade eletrocortical e vias apoptóticas cerebrais durante choque hemorrágico. MÉTODOS: Animais anestesiados com isofluorano foram submetidos ao choque hemorrágico [grupo Hemo; pressão arterial média (PAM) de 40 mmHg por 30 minutos] e tratados com Ringer lactato (RL) (3RL; 3x volume de sangue removido), terlipressina (grupo Terli; bolus) ou SSH (grupo SSH; 4 mL/kg bolus) e comparados ao grupo Sham. Um modelo porcino (n = 56) foi utilizado para avaliação da pressão de perfusão cerebral (PPC) e de oxigênio tecidual (PbtO2), e da expressão cerebral de marcadores teciduais da regulação de água (aquaporina-4), sódio (cotransportador-1 de Na-K-2Cl), estresse oxidativo (substâncias reativas ao ácido tiobarbitúrico e superóxido dismutase dependente de manganês) e apoptose. Um modelo murino (n = 179) foi utilizado para avaliação da microcirculação (fluorescência de FITC-dextrano) e função mitocondrial (potencial redox e de membrana mitocondrial, utilizando-se a fluorescência de flavoproteínas endógenas e do tetrametilrodamina metil éster, respectivamente) no córtex cerebral, utilizando-se a microscopia confocal in vivo, e para avaliação da atividade eletrocortical cerebral, por meio da monitorização do potencial evocado somatossensorial. No modelo murino foram avaliados três grupos adicionais, constituídos pela associação da terlipressina ao RL (1x, 2x ou 3x volume removido). RESULTADOS: No grupo Hemo porcino, houve uma redução significativa da PPC e PbtO2, associada ao aumento na expressão cerebral de marcadores da regulação do transporte de água e sódio,...


INTRODUCTION: Small-volume resuscitation with hypertonic saline solution (HSS) or terlipressin can be an alternative to the administration of large amounts of crystalloids in haemorrhagic shock. The aim of this study was to evaluate the effects of HSS and terlipressin on cerebral perfusion and oxygenation and investigate the cerebral mechanisms associated with microcirculation, mitochondrial function, electrocortical activity and apoptotic pathways during haemorrhagic shock. METHODS: Isoflurane-anaesthetised animals were submitted to haemorrhagic shock [Haemo group; mean arterial pressure (MAP) of 40 mmHg for 30 minutes] and treated with lactated Ringer's solution (LR) (3LR group; 3x volume bled), terlipressin (Terli group; bolus) or HSS (HSS group; bolus 4 mL/kg) and were compared with a Sham group. A porcine model (n = 56) was used to assess the cerebral perfusion pressure (CPP) and tissue oxygenation (PbtO2) and the expression of tissue markers of water (aquaporin-4), sodium (Na-K-2Cl cotransporter-1), oxidative stress (thiobarbituric acid reactive substances and manganese superoxide dismutase) and apoptosis in cerebral samples. A murine model (n = 179) was used to assess microcirculation (FITC-dextran fluorescence) and mitochondrial function (redox and membrane potential, using the fluorescence of endogenous flavoproteins and tetramethylrhodamine methyl ester, respectively) in the cerebral cortex by using in vivo confocal microscopy, and to assess the electrocortical brain activity by monitoring the somatosensory evoked potential. In the murine model, three additional groups were evaluated, which received terlipressin associated to LR (1x, 2x or 3x blood withdrawn). RESULTS: In the porcine Hemo group, there was a significant decrease in the CPP and PbtO2, which were associated to an increased cerebral expression of markers of water and sodium transport...


Subject(s)
Female , Animals , Shock, Hemorrhagic , Hypoxia, Brain , Microcirculation , Mitochondria , Electrophysiology , Arginine Vasopressin
15.
Article in English | WPRIM | ID: wpr-67431

ABSTRACT

BACKGROUND: The beach chair position (BCP) is associated with hypotension that may lead to cerebral ischemia. Arginine vasopressin (AVP), a potent vasoconstrictor, has been shown to prevent hypotension in BCP. It also improves cerebral oxygenation in different animal models. The present study examined the effect of escalating doses of AVP on systemic hemodynamics and cerebral oxygenation during surgery in BCP under general anesthesia. METHODS: Sixty patients undergoing arthroscopic shoulder surgery in BCP under general anesthesia were randomly allocated to receive either saline (control, n = 15) or three different doses of AVP (0.025, 0.05, or 0.075 U/kg; n = 15 each) 2 minutes before BCP. Mean arterial pressure (MAP), heart rate (HR), regional cerebral oxygen saturation (SctO2), and jugular venous oxygen saturation (SjvO2) were measured after induction of anesthesia and before (presitting in supine position) and after BCP. RESULTS: AVP per se given before BCP increased MAP, and decreased SjvO2, SctO2, and HR in all patients (P 20% SctO2 decrease from the baseline value) with no differences in SjvO2 and the incidence of SjvO2 < 50% or SjvO2 < 40% among the groups. CONCLUSIONS: AVP ameliorates hypotension associated with BCP in a dose-dependent manner in patients undergoing shoulder surgery under general anesthesia. However, AVP may have negative effects on SctO2 before and after BCP and on SjvO2 before BCP.


Subject(s)
Anesthesia , Anesthesia, General , Arginine Vasopressin , Arterial Pressure , Brain Ischemia , Heart Rate , Hemodynamics , Humans , Hypotension , Incidence , Models, Animal , Oxygen , Shoulder , Vasopressins
16.
Article in English | WPRIM | ID: wpr-96084

ABSTRACT

BACKGROUND: Arginine vasopressin (AVP) is widely used as a vasopressor agent. Some recent studies have suggested that AVP may exert an immunomodulatory effect. However, the mechanism about the anti-inflammatory effect of AVP is not well known. We investigated the effect of AVP on the ihibitor of kappa B (IkappaBalpha)/nuclear factor-kappa B (NF-kappaB) pathway in RAW 264.7 cells. METHODS: Cultured RAW 264.7 cells were pretreated with AVP and stimulated with lipopolysaccharide (LPS). To evaluate the effect of AVP on inflammatory cytokines, the concentration of interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-alpha) were assessed by an enzyme-linked immunosorbent assay technique. The expression of IkappaBalpha and nuclear translocation of NF-kappaB p65 were measured by Western blotting, and IkappaB kinase (IKK) activity was analyzed by an in vitro immune complex kinase assay. To confirm the AVP effect on IkappaBalpha/NF-kappaB cascade and via V2 receptor, we added tolvaptan (V2 receptor antagonist) after AVP pretreatment. RESULTS: The increase of IL-6 and TNF-alpha in LPS-stimulated RAW 264.7 cells was suppressed by a treatment with AVP. Pretreatment of AVP inhibited increasing of IKK activity and IkappaBalpha degradation induced by LPS in RAW 264.7 cells. Furthermore, LPS induced and NF-kappaB transcription was inhibited by AVP pretreatment. The observed changes in IKK activity, IkappaBalpha degradation and NF-kappaB transcription by AVP was abolished by tolvaptan treatment. CONCLUSIONS: Our results suggest that AVP showed anti-inflammatory effect on LPS-induced IkappaBalpha/NF-kappaB cascade in mouse macrophages via V2 receptors.


Subject(s)
Animals , Antigen-Antibody Complex , Arginine Vasopressin , Blotting, Western , Cytokines , Enzyme-Linked Immunosorbent Assay , I-kappa B Kinase , Interleukin-6 , Macrophages , Mice , NF-kappa B , Phosphotransferases , Receptors, Vasopressin , Tumor Necrosis Factor-alpha
17.
Article in English | WPRIM | ID: wpr-149432

ABSTRACT

Impact of water intake on the courses of chronic kidney and urinary tract diseases, such as urolithiasis, urinary tract infections, chronic kidney diseases (CKD), autosomal dominant polycystic kidney diseases and bladder cancer, has recently been studied. It still remains controversial whether increased water intake slows the progression of CKD or not. However, high water intake suppresses plasma levels of arginine vasopressin (AVP), which is expected to be beneficial for the preservation of the kidney function. Previous studies suggest that water intake suppresses plasma levels of AVP, and high levels of AVP have been suggested to play deleterious roles in animal models of kidney disease. Moreover, recent epidemic of CKD of unknown origin, which was supposed to be related to the insufficient water intake and chronic volume depletion, has been reported in Central America, further suggesting that the suppression of AVP by sustained water intake might be beneficial in this CKD population. Indeed, the data from recent studies were consistent with the view that high water intake is associated with slower progression of CKD. However, contradictory findings also exist. The intriguing effects of increased urine volume in preserving the glomerular filtration rate in human patients with CKD require more large and well-designed randomized prospective clinical trials.


Subject(s)
Arginine Vasopressin , Central America , Dehydration , Drinking , Glomerular Filtration Rate , Humans , Kidney , Kidney Diseases , Models, Animal , Plasma , Polycystic Kidney, Autosomal Dominant , Prospective Studies , Renal Insufficiency, Chronic , Urinary Bladder Neoplasms , Urinary Tract Infections , Urolithiasis , Urologic Diseases , Water
18.
Korean Journal of Medicine ; : 558-562, 2015.
Article in Korean | WPRIM | ID: wpr-116378

ABSTRACT

Desmopressin diacetate arginine vasopressin (DDAVP) is a synthetic analogue of the arginine vasopressin that is widely used in the treatment of diabetes insipidus, nocturnal enuresis, and polyuria. Although it is generally well-tolerated, DDAVP can cause hyponatremia, especially in elderly patients. There are many reports of DDAVP-induced hyponatremia, but there has been only one case report in which sinus node dysfunction was caused by severe hyponatremia. Here we report a case of sick sinus syndrome that occurred during an episode of severe hyponatremia induced by chronic use of desmopressin in a 91-year-old man who had nocturnal enuresis.


Subject(s)
Aged , Arginine Vasopressin , Deamino Arginine Vasopressin , Diabetes Insipidus , Humans , Hyponatremia , Nocturnal Enuresis , Polyuria , Sick Sinus Syndrome
19.
Article in English | WPRIM | ID: wpr-16304

ABSTRACT

The kidney collecting duct is an important renal tubular segment for the regulation of body water and salt homeostasis. Water reabsorption in the collecting duct cells is regulated by arginine vasopressin (AVP) via the vasopressin V2-receptor (V2R). AVP increases the osmotic water permeability of the collecting duct cells through aquaporin-2 (AQP2) and aquaporin-3 (AQP3). AVP induces the apical targeting of AQP2 and transcription of AQP2 gene in the kidney collecting duct principal cells. The signaling transduction pathways resulting in the AQP2 trafficking to the apical plasma membrane of the collecting duct principal cells, include AQP2 phosphorylation, RhoA phosphorylation, actin depolymerization and calcium mobilization, and the changes of AQP2 protein abundance in water balance disorders have been extensively studied. These studies elucidate the underlying cellular and molecular mechanisms of body water homeostasis and provide the basis for the treatment of body water balance disorders.


Subject(s)
Actins , Aquaporin 2 , Aquaporins , Arginine Vasopressin , Body Water , Calcium , Cell Membrane , Homeostasis , Kidney Tubules, Collecting , Permeability , Phosphorylation , Vasopressins
20.
Arq. bras. med. vet. zootec ; 66(2): 609-612, Jan.-Apr. 2014. ilus
Article in English | LILACS | ID: lil-709304

ABSTRACT

O presente estudo apresenta o comportamento do gene HER2, a partir do uso da técnica de hibridização cromogênica in situ, em hiperplasias ductais atípicas associadas a carcinomas mamários caninos positivos para HER2. Aparentemente, uma fraca expressão da proteína HER2 foi observada nas hiperplasias ductais atípicas, bem como uma ausência de amplificação do seu gene codificador nessas hiperplasias e nos carcinomas mamários associados. O comportamento da proteína HER2 e do seu gene em carcinomas mamários caninos é similar ao observado em alguns subtipos histológicos de tumores mamários humanos, e a ausência dessas alterações sugerem que esse gene poderia aparentemente não estar envolvido com os estágios iniciais de proliferação celular atípica...


Subject(s)
Animals , Dogs , Carcinoma/genetics , Dog Diseases/pathology , /physiology , In Situ Hybridization/veterinary , Hyperplasia/genetics , Hyperplasia/veterinary , Arginine Vasopressin , Immunohistochemistry/veterinary , Mammary Neoplasms, Animal
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