Re: frog heart beats - 1920s?

[Muckerheide <muckerheide@attbi.com>]

Hi Ruth,



I'd have to do some digging. But if recall correctly this was done using

water with and without radium.



Regards, Jim





on 7/11/02 1:35 AM, Ruth Sponsler at jk5554@yahoo.com wrote:



> What is the cite for the frog dissection mentioned?

> (even if it's a 1-paragraph note in a 1920s journal).

> What was the isotope?

> 

> Was there possible contamination with Ca++ in a

> concentration that could induce beating after the

> heart of the frog had stopped beating?  The reason I

> mention this is that if RaCl2 were used back in the

> 1920s, and had been separated out using Mme. Curie's

> method, there was likely some CaCl2 present as well

> (in larger mole quantity than the Ra).

> 

> As it happens, Ca++ acts to regulate muscle

> contraction with actin, myosin, and ATP (the energy

> currency of cells).  From a web site about frog heart

> beats:

> 

> "Historical experiments: In 1883, Ringer observed that

> contraction of isolated frog heart ceases when CaCl2

> was omitted from the bathing solution. This was

> reversible."  (Ringer, of Ringer's soln.)

> 

> Trying this (avoiding having any Ca++ present and

> perhaps using an isotope of an element that is not

> physiologically active) sounds like something for a

> 'non-squeamish' science fair participant??

> 

> 

> ~Ruth 2

> 

> (the froggy heartbeat link below is probably not

> interesting to most, but it's where the Ringer comment

> came from)

> http://www.uic.edu/classes/phyb/phyb516/regulationmusclecontru3.htm

> 

> 

> 

>> Ionizing radiation is essential for biology to

>> function. In the early 2oth

>> Century experiments such as dissecting a frog to

>> provide access to the

>> heart, and after death (heart stopping after brain

>> death), a drop of water

>> with radioactivity restarted the heart.

> 

>> Regards, Jim Muckerheide

>> ========================

> 

> 

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