U1 day 8 stress

Question 1

Receptor translocation

Answer 1

genomic effects involve transcriptional repression and/or activation. GRE: glucocorticoid response elements regulate hundreds of genes.

Question 2

parts of GR (glucocorticoid receptor)

Answer 2

Ligand binding domain (LBD), Hinge: allows for conformational change, DBD: DNA binding domain, N-terminus: contains nuclear localization sequence and Dimerization domain.

Question 3

which domain of the glucocorticoid receptor directly mediates interactions with cortisol?

Answer 3

Ligan biding domain, this is what it binds to on the membrane of cell

Question 4

SPG (steroid binding globulin)

Answer 4

in blood outside of cell, buffers circulating glucocorticoids from activating all signals all the time, but keeps them ready to respond when needed.

Question 5

Stopping HPA axis

Answer 5

receptor in membrane receives signal, stops by binding to receptor to suppress the fast acting response which produces cortisol

Question 6

Feedback to HPA axis

Answer 6

mediated by GR and MR, negative feedback occurs at hypothalamic CRH neurons and pituitary corticotropes, cortical hippocampal GR and MR also provide negative feedback to stop signal

Question 7

Which process is most likely to contribute to glucocorticoid receptor-dependent negative feedback?

Answer 7

Transcriptional repression of POMC in pituitary, this is what makes ACTH and causes the cortisol response. So less POMC, less ACTH, less cortisol, stop stress response.

Question 8

acute stress actions

Answer 8

Amino acid mobilization, immune suppression, elevated BP, Cognitive enhancing, memory enhancing.

Question 9

chronic stress actions

Answer 9

Insulin resistance, muscle weakness, abdominal obesity, reproductive deficits, hypertension, cognitive dysfunction, impaired negative feedback. reduction in dendrite size, decreased in neuronal complexity.

Question 10

Cushing syndrome

Answer 10

hypercortisolism, as a result of ACTH or adrenal cortical neoplasm, results in cognitive impairment, mood disorders, hypertension, cardiac hypertrophy, obesity, muscle weakness

Question 11

Addison’s Disease

Answer 11

Hypercortisolism, Autoimmune lose of cells in adrenal cortex. High ACTH because of lost negative feedback, adrenal crisis is a medical emergency and can be fatal.