How would it be possible to have the normal amount of a hormone circulating in the blood yet still have symptoms that indicate a shortage of that hormone?

The possible reason for the symptom of lack of hormone with the presence of hormone circulating has been lack of receptor susceptibility, or presence of hormone degrading enzyme.

Hormones are chemical messenger that travels in the bloodstream and performs various functions. The hormones are the proteins that act as signal transducers.

The presence of hormones in the bloodstream through experiencing symptoms of lack of hormone has been due to the lack of receptor susceptibility to detect the hormone.

Another factor that has been mediating the lack of hormones has been the degradation of the enzyme. The presence of enzymes or other substances degrades the hormones and results in the lack of detected hormones.

Thus, the hormone through being present in the blood has remained undetected due to lack of receptor susceptibility, or presence of hormone degrading enzyme.

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Answer/Explanation:

There are a few ways this could be possible.

It could be that the receptors in the cell that are supposed to recognise and respond to the hormone are not working (by mutation, shortage, or inhibited by another factor). Therefore, even though there is plenty of hormone circling, the hormone is unable to cause the normal signalling responses, because the receptor is not acting upon its binding. This could also be true for a variety of proteins involved in that particular pathway, maybe the receptor protein is working fine, but another protein in that pathway is malfunctioning.

Another option could be that for some reason the cell is targeting the hormone for degradation, meaning it is unable to carry out its functions even though it is present in the blood.

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