I was reading about pancreatic digestive enzymes in a Textbook of Medical Physiology and I came across Trypsin Inhibitor. The text stated that:

It is important that the proteolytic enzymes of the pancreatic juice not become activated until after they have been secreted into the intestine because the trypsin and the other enzymes would digest the pancreas itself.... ....substance called trypsin inhibitor. This substance is formed in the cytoplasm of the glandular cells, and it prevents activation of trypsin both inside the secretory cells and in the acini and ducts of the pancreas.

It also states that:

When first synthesized in the pancreatic cells, the proteolytic digestive enzymes are in the inactive forms trypsinogen, chymotrypsinogen, and procarboxypolypeptidase, which are all inactive enzymatically. They become activated only after they are secreted into the intestinal tract.

My question is, why is Trypsin Inhibitor secreted if trypsin is already secreted as trypsinogen which can only be activated in the intestine?

  • 1
    $\begingroup$ I think this is a pertinent question, which deserves more attention. My own brief survey suggests that there is no simple answer. If nobody else answers I'll summarize what I can find when I have a moment. $\endgroup$
    – David
    Commented Oct 7, 2020 at 9:55
  • $\begingroup$ @David As you say, it is not an easy answer. It's a matter of time. $\endgroup$
    – Chris
    Commented Oct 7, 2020 at 10:02
  • $\begingroup$ @Chris I’m not blaming anyone. Just trying to draw attention and let the poster know that he might have to wait for a proper answer. $\endgroup$
    – David
    Commented Oct 7, 2020 at 11:38
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    $\begingroup$ I’m voting to close this question because it is cross-posted with an answer at: medicalsciences.stackexchange.com/questions/24834/… Please see meta.stackexchange.com/questions/64068/… $\endgroup$
    – Bryan Krause
    Commented Oct 7, 2020 at 14:53
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    $\begingroup$ @BryanKrause — Thanks for noticing that, and saving me spending my time duplicating someone else’s work. Which is one good reason why cross-posting is anti-social. $\endgroup$
    – David
    Commented Oct 7, 2020 at 22:04