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[Neuroscience] Re: Brain impedance

Ana.Cervera-Ferri from uv.es via neur-sci%40net.bio.net (by Ana.Cervera-Ferri from uv.es)
Wed Jun 20 13:47:44 EST 2007


Thank you for your advises, I will measure it. We have a voltage clamp
system isolation unit but I haven't had the time to try it yet. By the
time I am working in the voltage-response curve to determine the useful
 voltage. 

Ana


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> Today's Topics:
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>    1. Re: Brain impedance (aeneurofisiologia from gmail.com)
>    2. Re: Fundamental Concepts of Neuroscience (Mathias)
>    3. Re: Stress Medication (Mathias)
>    4. Rat brain atlas (punnu bansal)
>    5. Re: Fundamental Concepts of Neuroscience (Francis Burton)
>    6. Re: Rat brain atlas (Shawn Mikula)
>    7. Re: Brain impedance (Bill)
>    8. Stationary Noise analysis for single-channel info? (Bill)
> 
> 
> ----------------------------------------------------------------------
> 
> Message: 1
> Date: Tue, 19 Jun 2007 13:15:07 -0000
> From: "aeneurofisiologia from gmail.com" <aeneurofisiologia from gmail.com>
> Subject: [Neuroscience] Re: Brain impedance
> To: neur-sci from net.bio.net
> Message-ID: <1182258907.711715.4030 from n2g2000hse.googlegroups.com>
> Content-Type: text/plain; charset="us-ascii"
> 
> 
> <Ana.Cervera-Fe... from uv.es> escreveu:
> > Hi all,
> >
> > I want to stimulate through bipolar teflon-coated steel electrodes in
> > the tegmentum in rats with pulses of 50-500 uA. I need to know which is
> > the average brain impedance in vivo to calculate the voltage needed. I
> > suppose that the contribution of the electrode impedance is low but if I
> > have to take it into account any advise is welcome.
> > Thank you in advance!
> >
> > Ana
> 
> Hi am a student of neurophysiology, I'm Portuguese and I will respond
> to you in Spanish.
> la impedansia es una ressistensia que varia com el tiempo, tiens
> varios problemas el primero es que es mui variable de ser vivo para
> ser vivo y es distinto em um ser vivo mediante la estructura e el
> momento em que asses la medicion de la impedancia.
> bueno lo que te aconserro es que agas lo siguente la maioria de los
> aparatos de EEG o EMG tienes lector de inpedancia de esse modo puedes
> seber la impedancia de la estructura que queres estimular em un
> momento dado, normalmente la enpedansia dada por la maquina ja tiene
> em cuenta la ressistensia del electrodo porque este no esbariable.
> 
> Buena suerte e espero tenerte ajudado
> 
> 
> 
> ------------------------------
> 
> Message: 2
> Date: Tue, 19 Jun 2007 15:21:57 +0200
> From: Mathias <mathiasDOTfranzius from webDELETEME.de>
> Subject: [Neuroscience] Re: Fundamental Concepts of Neuroscience
> To: neur-sci from net.bio.net
> Message-ID: <f58l9l$mve$1 from hahn.informatik.hu-berlin.de>
> Content-Type: text/plain; charset=ISO-8859-1; format=flowed
> 
> Umesh wrote:
> > I want a gist of fundamental concepts of neuroscience, Can you help
> > me? Thank you for your attention.
> > 
> 
> If you're looking for books, I can recommend these two:
> 
> http://books.google.com/books?id=moCkAAAACAAJ&dq=handbook+arbib
> http://books.google.com/books?id=vbS_AgAACAAJ&dq=kandel+shwartz
> 
> Mathias
> 
> 
> ------------------------------
> 
> Message: 3
> Date: Tue, 19 Jun 2007 15:24:54 +0200
> From: Mathias <mathiasDOTfranzius from webDELETEME.de>
> Subject: [Neuroscience] Re: Stress Medication
> To: neur-sci from net.bio.net
> Message-ID: <f58lf6$mve$2 from hahn.informatik.hu-berlin.de>
> Content-Type: text/plain; charset=ISO-8859-1; format=flowed
> 
> Please do not post your homework assignments in news groups. You won't 
> learn anything but instead unnerve many people.
> 
> 
> ------------------------------
> 
> Message: 4
> Date: Tue, 19 Jun 2007 03:48:26 -0700 (PDT)
> From: punnu bansal <punnubansal79 from yahoo.com>
> Subject: [Neuroscience] Rat brain atlas
> To: neur-sci from magpie.bio.indiana.edu
> Message-ID: <502746.74674.qm from web31001.mail.mud.yahoo.com>
> Content-Type: text/plain; charset=iso-8859-1
> 
> dear sir 
>    
>    
>   we need rat atlas for our study so please send me the detail of rat
atlas from where it is available 
> 
> 
>   Puneet Kumar Bansal 
> M.Pharma(Pharmacology) 
> H.No. B-XI  1103, Street No. 3, 
> KC Road, Barnala, 
> Punjab 148101, 
> India
>   MOBILE- 09876100692
> 
> 
>        
> ---------------------------------
> Pinpoint customers who are looking for what you sell. 
> 
> ------------------------------
> 
> Message: 5
> Date: 19 Jun 2007 17:15:15 GMT
> From: fburton from nyx.net (Francis Burton)
> Subject: [Neuroscience] Re: Fundamental Concepts of Neuroscience
> To: neur-sci from net.bio.net
> Message-ID: <1182273315.403667 from irys.nyx.net>
> 
> In article <1182269391.082140.195900 from g37g2000prf.googlegroups.com>,
> Umesh  <fraternitydisposal from gmail.com> wrote:
> >Is there any short book or summary work not more than few hundred
> >pages on the same?
> 
> It may be longer than you want, but I heartily recommend
> "An Anatomy of Thought" by Ian Glynn (Oxford University
> Press, 2003) as an extremely readable and erudite survey
> of the fundamentals.
> 
> http://tinyurl.com/2qgha3
> 
> Francis
> 
> 
> ------------------------------
> 
> Message: 6
> Date: Tue, 19 Jun 2007 15:56:02 -0700
> From: "Shawn Mikula" <samikula from ucdavis.edu>
> Subject: Re: [Neuroscience] Rat brain atlas
> To: <neur-sci from magpie.bio.indiana.edu>
> Message-ID: <004801c7b2c5$031619f0$3b867880 from mikulalaptop>
> Content-Type: text/plain; format=flowed; charset="iso-8859-1";
> 	reply-type=original
> 
> http://brainmaps.org
> 
> 
> ----- Original Message ----- 
> From: "punnu bansal" <punnubansal79 from yahoo.com>
> To: <neur-sci from magpie.bio.indiana.edu>
> Sent: Tuesday, June 19, 2007 3:48 AM
> Subject: [Neuroscience] Rat brain atlas
> 
> 
> > dear sir
> >
> >
> >  we need rat atlas for our study so please send me the detail of rat
atlas 
> > from where it is available
> >
> >
> >  Puneet Kumar Bansal
> > M.Pharma(Pharmacology)
> > H.No. B-XI  1103, Street No. 3,
> > KC Road, Barnala,
> > Punjab 148101,
> > India
> >  MOBILE- 09876100692
> >
> >
> >
> > ---------------------------------
> > Pinpoint customers who are looking for what you sell.
> > _______________________________________________
> > Neur-sci mailing list
> > Neur-sci from net.bio.net
> > http://www.bio.net/biomail/listinfo/neur-sci 
> 
> 
> 
> ------------------------------
> 
> Message: 7
> Date: Tue, 19 Jun 2007 21:39:51 -0700
> From: Bill <connelly.bill from gmail.com>
> Subject: [Neuroscience] Re: Brain impedance
> To: neur-sci from net.bio.net
> Message-ID: <1182314391.530453.216060 from x35g2000prf.googlegroups.com>
> Content-Type: text/plain; charset="us-ascii"
> 
> Three answers.
> 1) If you want to stimulate using a known current, buy a constant
> current stimulator. This is the only way to be certain. Electrode
> resistances change over time due to electroplating, oxidation etc.
> However there is nothing wrong with using a constant voltage
> stimulator. None of us can know the resistance of your stimulating
> electrode, I would not assume it is negligible, especially if it is
> fine at the end.
> 
> 2) Measure it! Next time someone culls an animal in your department,
> see if you can use the brain. All you'll need is a $20 dollar
> multimeter to get a pretty good idea of the resistance of your
> electrode when it is implanted in brain.
> 
> 3) 50-500uA? Do you actually -need- to be in that range? Surely you
> can just work up from 5V up to 20-100V, until you get the result you
> are looking for? Indeed, a nice input-output curve (stimulus vs
> response) graph is a nice way to indicate your intervention is truly
> due to your stimulus and not the implantation/surgery.
> 
> On Jun 18, 7:26 am, <Ana.Cervera-Fe... from uv.es> wrote:
> > Hi all,
> >
> > I want to stimulate through bipolar teflon-coated steel electrodes in
> > the tegmentum in rats with pulses of 50-500 uA. I need to know which is
> > the average brain impedance in vivo to calculate the voltage needed. I
> > suppose that the contribution of the electrode impedance is low but if I
> > have to take it into account any advise is welcome.
> > Thank you in advance!
> >
> > Ana
> 
> 
> 
> 
> ------------------------------
> 
> Message: 8
> Date: Tue, 19 Jun 2007 21:50:01 -0700
> From: Bill <connelly.bill from gmail.com>
> Subject: [Neuroscience] Stationary Noise analysis for single-channel
> 	info?
> To: neur-sci from net.bio.net
> Message-ID: <1182315001.872339.235600 from x35g2000prf.googlegroups.com>
> Content-Type: text/plain; charset="iso-8859-1"
> 
> Hi,
> 
> If I've got a standing background noise in a whole-cell voltage clamp
> experiment that I know is mediated by an ion channel (it goes away in
> the presence of all the right drugs and is enhanced by the right drugs
> etc), I am sure I can get some information on the single channel
> conductances that are making this noise.
> 
> I can find several papers that say things like "Given Variance^2 =
> i^2npo(1-po) we calculated a lorentzian function and found the single
> channel conductance".
> 
> How do I ACTUALLY do this? Anyone know? I'm sure I could get a graph
> program to fit a lorentzian function to a curve, if I could calculate
> the right curve in the first place, which is a spectral density
> function, which plots A^2/Hz vs Hz.
> 
> Does anyone have any idea what I'm talking about? (I certainly don't).
> Can anyone offer some rough tips on what I need to do? I have access
> to CED software, MiniAnalysis and John Dempsters WinWCP package.
> 
> 
> 
> ------------------------------
> 
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> End of Neur-sci Digest, Vol 25, Issue 8
> ***************************************
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> 


--

********************************
Ana Cervera Ferri
Dep Anatomía y Embriología Humana
Fac. Medicina y Odontología
Universitat de València
Av. Blasco Ibañez 15
46010-Valencia-Spain
tlf (+34) 963983507; 658159181
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