Question

What does low serum corticosterone, but high plasma ACTH indicate in stressed rats?​

Answer 1

Answer:

Explanation:

Elevated ACTH but low CORT is sometimes seen in rodent models of post-traumatic stress disorder (only in males though, are you using males? There are significant sex differences in the HPA axis response to stress). Diminished CORT release in response to stress could be due to a sensitization (or increase in number) of glucocorticoid receptors (GR) in the pituitary, and if all GR are saturated with ligand, no more suppression of ACTH can occur so that's where you can get high ACTH and low CORT. Due to this, the adrenal glands can become insensitive to ACTH--you can quantify ACTH receptors or just give them an ACTH injection and measure their CORT response to see.

Answer 2

Explanation:

Elevated ACTH but low CORT is sometimes seen in rodent models of post-traumatic stress disorder (only in males though, are you using males? There are significant sex differences in the HPA axis response to stress). Diminished CORT release in response to stress could be due to a sensitization (or increase in number) of glucocorticoid receptors (GR) in the pituitary, and if all GR are saturated with ligand, no more suppression of ACTH can occur so that's where you can get high ACTH and low CORT. Due to this, the adrenal glands can become insensitive to ACTH--you can quantify ACTH receptors or just give them an ACTH injection and measure their CORT response to see..

hope it's help you✔