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Juerg Feldmann

Fortiori Design LLC
Posts: 1,530

 There  is a   short add on to this blog  on the main page.
  One of the " dreams"    would be  to be able to  differentiate  between O2   used  and taken  or reloaded  to Mb   and Hb.  As  mentioned in the Blog ,  we  can't  do that  ( yet ). So  any change in  SmO2  will keep the question open  from where we  may the O2  .
  : Where is it coming  from?.
  Physiologically we  have some possible answers.
  O2  from Mb  is  designed  to help in " emergency"  situation.  meaning, in situation, where we  have a reduced  delivery over the blood.
  There  are  2  situations, where we have this.
 1.  At the start of  a  movement or activity  out  of a  "cold" start  . :
  HR ( cardiac  output)  as well as  respiration, as  2  of the main delivery systems  are  not yet fully    at performance load. As well at the end of a survival  situation to try to hang on, when  vital organs  are pushed  to  their own limit  and  ECGM  ( or CG )  will try to help you  to survive.  So  as the delivery  to the  extremity muscles  are getting   very low  or even  stops, due to  maintenance  of ATP levels in the more important   organs, we  will dig into   any O2  we  may still have locally.  If  we get there super low  we have the   picture  of  Rhabdomyolosis  as  a  sign of complete overload and  depletion of  energy source  of the muscles  with  destruction of  the   muscles  itself in extreme cases.
  So  when you look at the total  O2  diss curve you can see this situation, where  and when affinity of O2  is  better    to be released from Mb.
 As  in the blood  nicely written. ( see in red below )

However, the location of the molecules along the diffusion pathmust also be considered.

myoglobin blog image1 resized 600


Myoglobin is generally much closer to the mitochondria than the hemoglobin is, as it is found inside the muscle cell, whereas hemoglobin is found inside the red blood cell (See the sketch below. The O2 symbols represent the level of dissolved oxygen). 
My  add on .  O2    loaded on Mb  is much closer  to the site, where it can be used, than  O2  loaded  on Hb.  so in  stress situations, where energy is  immediately  needed    the  body will take the closest  energy  available  , which is  the O2  on Mb.  As   at the rest or start situation the  O2  diss curve of  Mb is more right than Hb  it is  not just closer, but even easier  to get.

describe the image

Oxygen from the hemoglobin has to diffuse out of the red blood cell, through the plasma, capillary wall, interstitial fluid, and into the muscle cell. O2   from the Mb is  sitting just there   with less affinity  at the start When there is a high rate of oxygen diffusion, the level of dissolved oxygen could be much lower around the myoglobin. This means that it is uncertain whether the hemoglobin or myoglobin is deoxygenating first. It might be helpful to know the hemoglobin and myoglobin oxygenation states separately, but the current state of the technology situationquo;t allow that.

So what we did  we  created a wheretio, hwere we  would  keep delivery  CO  and  actually; up  but  stop  to  muscles use the O2   from working Thanels . load  musclesgain the working beyond.
 So basically we  would  keep a delivery  above  and theong what its needed in wormusclesng thecel but as well use high2   from respiratoryac  and  activitytory a thanity, musclesbsp; start again   activityad  and reduce  respiratory  and cardiac  whenvityu to see,   whether maintainsp; notnaitain delivery we  would drop see a d the in SmO2   due  to need local taking  O2  from the storagetsroage  ) Mb  and musclesp; still loaded in active thecel.
 The result  where  great no change in SmO2  level  despite a severe change in load and unload  form the muscular  side.
  Will show  some of studtheuied  in commingt  few weeks.  as  I have some people theming over  holiday  to repeat seeh   task  independent  form me  to se,w theyher the  can replicate resultsp; resutl.

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