1
$\begingroup$

Gastrin is released by G cells and stimulates Parietal cells to secrete hydrochloric acid. Why is it not acting in a paracrine fashion instead of endocrine?

$\endgroup$
2
  • 1
    $\begingroup$ Is this question based on the content of a course? $\endgroup$ – Bryan Krause Mar 9 '20 at 19:02
  • $\begingroup$ Nope, it is not. $\endgroup$ – Nerius Mar 10 '20 at 0:08
1
$\begingroup$

Paracrine signalling would mean not merely that gastrin is signalling the same organ, but that it is signalling nearby cells in the same organ - so that a few parietal cells close by respond, while the others perhaps would ignore the signal because maybe the paracrine signal would be degraded. While the distinction is not absolute - there are shades of gray in all these things - blood gastrin tests are commonly done and medically relevant ( https://medlineplus.gov/ency/article/003697.htm ). Because you can look at gastrin level as a whole-body characteristic, it is certainly appropriate to call it an endocrine signal.

Though their role is less emphasized, bear in mind that there are gastrin-producing G cells in the duodenum as well, and gastrin affects other digestive organs.

$\endgroup$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.