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Objective To observre the change of plasma arginine vasopressin(AVP)in plasma and relationship of AVP with brain edema after traumatic brain injury(TBI).Methods The rat models of mild and severe degree local cerebral cortex injury were caused by free dropping.Radioimmunoassay was used to measure serial concentration of AVP in plasma in 45 rats with acute brain injuries at the 24th,48th,72th hour and the 5th day after brain injury.The content of injury brain water was measured by drying-wetting way.Results AVP levels had positive correlation with the severity of brain edema.The severer brain injury resulted in higher AVP level and longer persistent time of peak brain edema(P＜0.05).Conclusion AVP level is closely associated with edema after TBI.AVP may play a vital role in pathogenesis of brain edema.
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We present a case of severe hyponatremia in a 64-year-old man who had a pituitary tumor. He had nausea and recurrent vomiting with a severe headache, and was admitted to Chungnam National University Hospital for further evaluation. On physical examination, he was alert, and had bitemporal hemianopsia. There was no indication of dehydration or edema. Laboratory data showed a serum sodium level of 126 mEq/L, plasma osmolality of 259 mOsm/kg, and urinary osmolality of 544 mOsm/kg. The plasma argipressin level was 2.88 pg/mL, despite marked hyposmolality. Otherwise, pituitary function was normal. Brain magnetic resonance imaging showed a pituitary macroadenoma measuring 25x16x13 mm and no visible normal pituitary stalk or gland in the sella turcica. After the adenomectomy, the serum sodium level maintained normal without treatment. Histology showed the presence of a pituitary adenoma. These findings indicate that a non-functioning pituitary tumor may cause the exaggerated secretion of argipressin, resulting in inappropriate antidiuretic hormone syndrome.
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Humans , Middle Aged , Arginine Vasopressin , Brain , Dehydration , Edema , Headache , Hemianopsia , Hyponatremia , Inappropriate ADH Syndrome , Magnetic Resonance Imaging , Nausea , Osmolar Concentration , Physical Examination , Pituitary Gland , Pituitary Neoplasms , Plasma , Sella Turcica , Sodium , VomitingABSTRACT
Anatomical lesions of hypothalamic area associated with hypodipsic hypernatremia have been reported only rarely. We report here a case of hypodipsic hypernatremia induced by a hypothalamic lesion. A 25-yr-old man, who had been treated with radiation for hypothalamic tumor 5-yr before, was admitted for evaluation of hypernatremia and hypokalemia. He never felt thirst despite the elevated plasma osmolality and usually refused to drink intentionally. Plasma arginine vasopressin (AVP) level was normal despite the severe hypernatremic hyperosmolar state and urine was not properly concentrated, while AVP secretion was rapidly induced by water deprivation and urine osmolality also progressively increased to the near maximum concentration range. All of these findings were consistent with an isolated defect in osmoregulation of thirst, which was considered as the cause of chronic hypernatremia in the patient without an absolute deficiency in AVP secretion. Hypokalemia could be induced by activation of the renin-angiotensin-aldosterone system as a result of volume depletion. However, inappropriately low values of plasma aldosterone levels despite high plasma renin activity could not induce symptomatic hypokalemia and metabolic alkalosis. The relatively low serum aldosterone levels compared with high plasma renin activity might result from hypernatremia. Hypernatremia and hypokalemia were gradually corrected by intentional water intake only.
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Adult , Humans , Male , Arginine Vasopressin/metabolism , Hypernatremia/etiology , Hypothalamic Neoplasms/metabolism , Osmolar Concentration , ThirstABSTRACT
AIM: To explore the mechanism of Nao-re-qing oral liquid (NRQ) decreasing endotoxin (ET)-induced fever in rabbits. METHODS: (1) The ET-induced fever model was established in rabbits. Febrile response of rabbits was observed. (2) The arginine vasopressin (AVP) content in the ventral septal area (VSA),and cAMP content in hypothalarmus (HP) and CSF were determined by radioimmunoassay.RESULTS: (1) In ET group,the maximal increment in body temperature (?T) [(1.80?0.16) ℃],6 h thermal respone index (TRI_6)(11.31?0.20),the cAMP content in the HP [(1.35?0.21)nmol/g],the cAMP content in CSF [(66.69?1.82) nmol/L] and AVP content in the VSA [(30.80?9.59)ng/g ] were significantly higher than those in NRQ+ET group[?T(0.82?0.08) ℃,TRI_6(5.73?0.09),HP: cAMP(0.70?0.50)nmol/g,CSF: cAMP(56.86?1.34),AVP:(11.91?3.47)ng/g]( P
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AIM: To explore the antipyretic mechanism of Qing Kai-Ling (QKL) injection on endotoxin (ET)-induced fever in rabbits. METHODS: Rabbit models of endotoxin (ET)-induced fever were duplicated. The rectal temperature was measured by digital thermograph. The cAMP and IL-1? content in the hypothalamus (HP), the cAMP content in the cerebrospinal fluid (CSF), and the arginine vasopressin (AVP) content in the ventral septal area (VSA) were determined by radioimmunoassay. RESULTS: ① QKL had significant antipyretic effect on ET-induced fever( P
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AIM: To investigate the role of the nucleus tractus solitarius (NTS) in the regulation of paraventricular nucleus (PVN) AVP-ergic neurons on gastric ischemia- reperfusion injury (GI-RI). METHODS: Male SD rats were used in experiments. The celiac artery were clamped for 30 min and reperfused 1 h by removal of the clamp to obtain the ischemia-reperfusion state. The mechanism was analysed with nucleus electrical stimulation, electrolytic lesion and nucleus microinjection technique. RESULTS: Microinjection of arginine-vasopressin (AVP) into PVN obviously attenuated the GI-RI and dose-dependent effects were observed ( r= -0.477, P
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Objective: To observe the content of AVP changes in brain regions and pituitary of intracerebral hemorrhagic rats before and after treatment by ? sodium aescinate. Methods: Animal model was established by injecting collagenase into left caudoputamen of adult rats. Radioimmunoassay(RIA) was performed to measure the content changes of AVP, dye wet Weight methods was used to measure the changes of water contents in brain. Results: Compared with control group, the water content was increased significantly ( P
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Objective To investigate the relationship between the disorder of learning and memory in lead rats and the argnine vasopressin (AVP) and the somatotatin (SS) of hippocampus.Methods Sixty healthy 2-month old Sprague-Dawley rats were randomly divided into normal control group and lead group. Normal control group was given deionized water and the lead group was given 0.1% lead acetate deionized water for 3 months to make chronic lead rat. Learning and memory ability was tested by the Y-maze test. The content of AVP and SS in hippocampus were tested by the immunohistochemical method. Results The learning memory ability and the content of AVP and SS in hippocampus CA1 section of the lead group were degraded obviously than the control group(all P0.05)in hippocampus CA3 section of the lead group were degraded also.Conclusion The disorder of the learning and memory of the lead exposure rats may be due to the decrease of the content of AVP and SS in hippocampus.
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The effects of the destruction of the periaqueductal gray matter(PAG)on the memory-enhancement by intraperitoneal injection of arginine vasopressin(AVP)were observed in rats.Rats with either sham lesions or electrolytic destruction of the bilateral PAG were trained in a shuttle box for active avoidance response(AAR).After the rats met the criterion of 80% correctness,an intraperitoneal injection of 6?g/kg of AVP or 0.2ml of saline was given.Extinction of AAR was assessed in the rats.It was found that AVP markedly retarded the extinction of AAR in rats with sham lesion,and the extinction of the rats with destroyed PAG was significantly faster than that of the rats with sham lesion.The above mentioned findings suggest that AVP can act on the central nervous system to enhance memory mediated probably through PAG.This observation provides further support for the suggestion that certain limbic midebrain structures are involved in the memory enhancement by AVP.
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AIM:The purpose of the present study was to investigate the effect of interleukin-10(IL-10)on the proliferation and calcineurin(CaN)activity in cultured cardiac fibroblasts(CFs)induced by arginine vasopressin(AVP).METHODS:The CFs of left ventricle in neonatal Sprague-Dawley rats were isolated and cultured by trypsin digestion and selective plating technique.Then the proliferation rates of cells were determined by using the MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay(A490 value).Cell cycle distribution was determined with flowcytometry technique.The CaN activity was measured by ultra-violet spectrophotography.RESULTS:(1)MTT colorimetry showed that 10-7 mol/L AVP significantly increased A490 value of CFs in comparison with control group(P
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AIM: To assess if endogenous arginine vasopressin is involved in normal thermoregulatory processes. METHODS: Core temperature was monitored in undisturbed rats using radiotelemetry. Effect of AVP V 1 antagonist on normal body temperature were observed in rats under a 12:12 light-dark cycle. RESULTS: Intraperitoneal injection of AVP V 1-receptor antagonist in rats induced a increase in normal body temperature. Under normal light (light on at 6:00 AM-6:00 PM), AVP V 1 antagonist induced a increase in body temperature persisting for about 6 hour, but male rats had higher hyperthermia than female. Under normal dark exposure (light off at 6:00 PM- 6:00 AM), AVP V 1-receptor antagonist caused a increase in body temperature persisting for about 2 hour at the start of the dark phase, but no difference was found between sexes. CONCLUSION: Intraperitoneal injection of AVP V 1-receptor antagonist caused a increase in normal body temperature. The data indicated that endogenous vasopressin could be involved in tonic thermoregulatory process.
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AIM: To investigate the mechanism of Qing-Kai-Ling(QKL) Injecta suppressing endotoxin(ET)-induced fever in rabbits.METHODS: ①The ET-induced fever model was established in rabbits. QKL injecta was administered intravenously, and the febrile response of rabbits was observed. The cAMP content in the hypothalamus (HP) and arginine vasopressin (AVP) content in the ventral septal area (VSA) were determined by radioimmunoassay.RESULTS: ①The maximal increment in body temperature (△T)[(1 68?0 46)℃],6 h thermal response index (TRI 6)(29 59?10 39), cAMP content in the HP[(2 90?0 40) nmol/g] and AVP content in the VSA[(47 32?3 77) ng/g] in the ET group were significantly higher than those in the normal saline (NS) group[(0 08?0 11)℃,-0.15?4 29,(1 05?0 37) nmol/g,(11 78?7 87) ng/g, respectively] and the QKL+ET group[(0 48?0 18)℃, (13.71?3.29), (1 37?0 23) nmol/g,(25 24?2 61) ng/g, respectively].②The positive correlation was observed between the cAMP content in the HP and the fluctuation of body temperature ( r=0.904,P
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AIM: To explore the effects of tumor necrosis factor-? (TNF-?) on inducible nitric oxide synthase (iNOS)-nitric oxide (NO) system activity in arginine vasopressin (AVP)-induced rat cardiac fibroblasts (CFs). METHODS: CFs were isolated by trypsin digestion method. Nitrate reductase method, spectrophotometry and reverse transcription-polymerase chain reaction (RT-PCR) were used to detect NO contents, NOS activity and iNOS mRNA expression, respectively. RESULTS: AVP significantly increased iNOS mRNA expression, NOS activity and NO contents in CFs. Combined with AVP, TNF-? enhanced the effects of AVP on iNOS-NO system activity in a concentration-dependent manner. However, if the concentration of TNF-? was too high, the iNOS-NO system activity did not increase accordingly, but slightly decreased instead. CONCLUSION: TNF-? stimulates iNOS-NO system activity in coordination with AVP in CFs. The enhancement of NO contents inhibits ventricular remodeling induced by AVP and TNF-?. [
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Plasma concentrations of ?-endorphin (?-EP), leucine enkephalin (L-EK), neurotensin (NT), arginine vasopressin (AVP), renin activity (PRA) and angiotensin Ⅱ (AT Ⅱ ) were measured by radioimmunoassay in 60 normal persons and 120 hypertensive patients. There were lower levels of ?-EP and L-EK (P
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Twenty cats were anesthetized and divided randomly into 3 groups: hemorrhagic shock (HS), electrical stimulation of the hypothalamic paraventricular nucleus (ESPVH) and hemorrhagic shock with addition to electrical stimulation of PVH (HS+ESPVH), so as to observe the change of plasma AVP during experimental period. The results showed that plasma AVP was increased to peak in the initial 5 min in all 3 group animals, and their values were 336.3?62.2 pg/ml (P
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Objective To explore the effect of arginine vasopressin(AVP) on proliferation and nitric oxide(NO) synthesis in rat cardiac fibroblasts(CFs). Methods CFs were isolated by trypsin digestion method. The effect of AVP on proliferation and NO synthesis were measured by MTT technique and nitric acid reductase method respectively. Results The MTT OD values of CFs increased in a concentration-dependent manner with the rising of the concentration of AVP and in a time-dependent manner with the prolongation of the culture time. For example, the MTT OD values of 10 -6 mol/L AVP group were higher than those of the control, and the MTT OD values of CFs cultured for 36h were significantly higher than those cultured for 6h when intervened with 10 -7 mol/L AVP. The content of NO of CFs displayed the same change as the MTT OD values. The contents of NO in 10 -7 mol/L and 10 -6 mol/L AVP groups were statistically higher than those of the contral group, 10 -9 mol/L AVP group and 10 -8 mol/L AVP group. The NO contents of CFs cultured for 24h and 36h were significantly higher than those cultured for 6h and 12h. Conclusion AVP can stimulate the proliferation of CFs and the synthesis of NO in neonatal rat. The enhancement of NO contents would inhibit CFs proliferation and myocardial fibrosis induced by AVP.