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A novel role for vasopressin in the brain modulation of a radial, activity dependent water flux

, : A novel role for vasopressin in the brain modulation of a radial, activity dependent water flux. Society for Neuroscience Abstracts 26(1-2): Abstract No -537 18

The brain contains an intrinsic vasopressin fiber system and astrocytes express high levels of a water channel, aquaporin-4 (AQP4). Since vasopressin is known to regulate AQP2 expression and translocation in kidney collecting ducts we hypothesize that vasopressin might have a similar function in the brain. Electrical stimulation of layer VI of the neocortex elicits a water flux towards superficial layers that is thought to accompany the spatial buffering of excess K+. Water redistribution was assessed by recording the intrinsic optical signal (IOS) which reflects changes in the extracellular volume. A distinct dark IOS (indicative of an extracellular volume increase) was recorded in the superficial layers and the tangential extent of this signal was enhanced by application of vasopressin or vasopressin V1a agonists. V1a antagonists abolished this effect and reduced the IOS size also in control conditions. V2 agonists and antagonists showed no effect. The vasopressin effect on water redistribution was abolished by thapsigargin and bisindolylmaleimide. The extracellular volume changes occurred within seconds after electrical stimulation suggesting that specialized water channels are involved. The distribution of AQP4 was analysed. AQP4 was concentrated in the subpial plasma membranes and in perivascular endfeet throughout the cortex. The subcellar distribution of this channel was not changed by vasopressin.


Other references

Bamberg, E.; Choi, H.S.; Mostl, E., 1986: Faecal oestrogen concentrations for pregnancy diagnosis in horses, cattle, pigs, sheep and goats. In horses, pregnancy diagnosis from measurement of faecal oestrogen was possible from 120 days of gestation. In 111 cows + heifers, pregnancy diagnosis from measurement of faecal oestradiol-17 alpha was possible in 7% of pregnant animals from wk 1...

D.V.gneaud V.; Meador J.D.; Ferger M.F.; Allen G.A.; Blomquist A.T., 1971: The synthesis and biological properties of 1 deamino penicillamine oxytocin deuterated in the 1 position. Bioorganic Chemistry 1(1-2): 123-128

Begnami, M.D.; Palau, M.; Rushing, E.J.; Santi, M.; Quezado, M., 2007: Evaluation of NF2 gene deletion in sporadic schwannomas, meningiomas, and ependymomas by chromogenic in situ hybridization. Fluorescence in situ hybridization, loss of heterozygosity testing, and comparative genomic hybridization have been used to detect NF2 gene alterations in both sporadic and neurofibromatosis type 2 (NF2)-associated central nervous system tumors....

Dybel, G.J.; Seymour, C.J., 1997: Identifying the physical demands of Army Reserve personnel during deployable medical systems training. The purpose of this investigation was to (1) assess the physical demands of soldiers involved in Deployable Medical Systems (DEPMEDS) activities, and (2) evaluate the incidence of musculoskeletal injuries among reserve military personnel involved...

Bach, J.F.; Chatenoud, L., 1983: Therapeutic use of monoclonal antilymphocyte antibodies. Presse Medicale 12(41): 2615-2618

Arnold N.; Wienberg J.; Ermert K.; Zachau H.G., 1991: Evolution of v kappa immunoglobulin genes in human and primates analysed by molecular cytogenetics. American Journal of Human Genetics 49(4 SUPPL): 332

Petit, P.; Bréard, J.; Montalescot, Vérie.;, N.Ben.; Levade, T.; Popoff, M.; Geny, B., 2003: Lethal toxin from Clostridium sordellii induces apoptotic cell death by disruption of mitochondrial homeostasis in HL-60 cells. Lethal toxin (LT) from Clostridium sordellii (strain IP82) inactivates in glucosylating the small GTPases Ras, Rap, Ral and Rac. In the present study we show that LT-IP82 induces cell death via an intrinsic apoptotic pathway in the myeloid cell-li...

Wan, C-Feng.; Chen, W-Hong.; Chen, C-Ta.; Chang, M.Dah-Tsyr.; Lo, L-Chiang.; Li, Y-Kuen., 2006: Mutagenesis and mechanistic study of a glycoside hydrolase family 54 alpha-L-arabinofuranosidase from Trichoderma koningii. A GH (glycoside hydrolase) family 54 alpha-L-arabinofuranosidase from Trichoderma koningii G-39 (termed Abf) was successfully expressed in Pichia pastoris and purified to near homogeneity by cation-exchange chromatography. To determine the amino a...

Yang, T.; Liu, J.; Yang, M.; Huang, N.; Zhong, Y.; Zeng, T.; Wei, R.; Wu, Z.; Xiao, C.; Cao, X.; Li, M.; Li, L.; Han, B.; Yu, X.; Li, H.; Zou, Q., 2016: Cucurbitacin B exerts anti-cancer activities in human multiple myeloma cells in vitro and in vivo by modulating multiple cellular pathways. NlmCategory="UNASSIGNED">Cucurbitacin B (CuB), a triterpenoid compound isolated from the stems of Cucumis melo, has long been used to treat hepatitis and hepatoma in China. Although its remarkable anti-cancer activities have been repo...

Rothfus, Ca, 1974: Closing the energy gap. Annual technical conference proceedings: 6-23