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Define: endocrine, neuroendocrine, paracrine, and autocrine; phosphorylation; amplification; 7 transmembrane domain receptor; trimeric G protein (alpha, beta and gamma subunits); Gs and Gi; adenylyl cyclase; ATP; cAMP; PKA (R and C domains), PKG, PKC, CaMK, PTK; phosphodiesterase; protein phosphatase; Ca signaling: PIP2, PLC, DAG, IP3, IP3R, SERCA, PMCA; lipid messengers (arachidonic acid, prostaglandins, leukotrienes); nitric oxide as signaling molecule.
What are the roles of kinases, ATP, phosphorylation, phosphatases, dephosphorylation and ATP in controlling cellular activities? Draw the relevant chemical reactions.
Three main amplifier enzymes are ____, which forms cyclic AMP, _____, which forms cyclic GMP and ____ which converts a phospholipid into two different signaling molecules.
Receptors for signaling pathways may be found in the __, __ and __.
Hormone receptors and membrane transporters both exhibit all of the following except
specificity
saturation
competition
amplification
List two similarities and two differences between epinephrine receptor and a growth factor receptor (a tyrosine kinase).
Distinguish between mechanisms of action of aldosterone (steroid hormone) and antidiuretic hormone (peptide hormone) on kidney cells. Mention receptors, time course of effects and role of second messengers and protein phosphorylation vs changes in gene expression and protein synthesis.
Predict the effect of the following on epithelial cellular [cAMP], increase, decrease or no change.
Treatment with caffeine, phosphodiesterase inhibitor.
Activation of Gi.
Treatment with cholera toxin that ADP ribosylated Gs.
Treatment with an activator of phospholipase C.
Treatment with insulin.
Treatment with a drug that inactivated PKA.
Treatment with a drug that increased cellular IP3.
T or F? cAMP activates PKA by phosphorylating the R domain.
T or F? PKA, PKG and PKC all bind ATP and catalyze the phosphorylation of serines and threonines on proteins.
T or F? Cytosolic [Ca] is approximately equal to extracellular [Ca], about 1 mM.
Phorbol esters are tumor promoters. Phorbol esters also have similar structures to diacylglycerol. Propose a signaling mechanism by which phorbol esters promote tumors.
Describe similarities and differences between:
Ca transporting properties of PMCA vs SERCA
Activation mechanisms of calmodulin and PKA
Second messenger functions of NO and calmodulin
Okadaic acid (a phosphatase inhibitor) and cholera toxin both lead to diarrhea. Offer a possible explanation based on effects of these agents on cAMP signaling.
Propose a teleological reason explaining why Ca2+ is used as a second messenger, while Na+ is not.
When steroid hormones act on the nucleus, the hormone/receptor complex acts as a /an ___, binds to DNA and activates one or more ___, which create mRNA and direct the synthesis of new __.
Know the following hormones, including whether they are steroid or peptide hormones, the cell that produces them, what controls their release, and effects they have on their target cells: aldosterone, insulin and glucagons (including the effects on metabolic pathways), parathyroid hormone and calcitonin, antidiuretic hormone and oxytocin, thyroid hormone, growth hormone and cortisol.
Distinguish among TRH, TSH, tyrosine, thyroglobulin, and thyroxine
Be able to identify the hypothalamus, anterior pituitary, posterior pituitary and blood supplies (including hypothalamic-hypophyseal portal system) in a diagram like Fig. 7-16 in the text.
Distinguish among glycolysis, glycogenolysis, gluconeogenesis, lipolysis and lipogenesis; also energy production by Krebs cycle and production of CO2 vs anaerobic glycolysis and lactic acid production.
Know: effects of insulin, glucagon, cortisol, growth hormone and epinephrine on glucose and amino acid concentrations in the blood, and how these effects are mediated.
primary storage places of glycogen
primary source of blood glucose in fasted state
Define synergism, antagonism and permissive (pp 226-227 text).
Know:effects of parathyroid hormone on blood [Ca], and effects on bone and kidneys and intestines
Roles of calcitriol and calcitonin in Ca2+ metabolism
Write A next to statements that apply to the anterior pituitary and P next to statements that apply to posterior pituitary.
T or F? Defend your answer. The adrenocorticosteroid hormones like cortisol are useful in fight or flight situations such as being chased by a bear.
T or F? Defend your answer. Endocrine gland cells that synthesize steroid hormones have lots of rough endoplasmic reticulum and hormone stored in vesicles.
A woman has secondary hypocortisolism due to a pituitary problem. If you give her ACTH, what happens to her cortisol secretion? Draw the complete control pathway with hormones and the glands as part of your answer.
In a person with inadequate iodine, how do levels of TRH, TSH and thyroxine compare to normal? Contrast these to a person with Graves disease.
What are the roles of glucose transporter, cellular and extracellular glucose concentrations, ATP, membrane voltage and Ca channels in the release of insulin from pancreatic beta cells?
Distinguish between diabetes Types 1 and 2 in terms of: blood [glucose] and [insulin]; causes.
A sulfonylurea drug (inhibits K channels in pancreatic beta cells) was mistakenly given to a patient, who promptly passed out. Can you offer an explanation?
Why do diabetics often have metabolic acidosis?
What is the role of the extracellular Ca receptor in parathyroid cells in controlling blood and extracellular [Ca]?
Cushing's syndrome causes, like diabetes, a wide range of pathologies.
What are two common causes of Cushing's syndrome or disease?
What causes the hyperglycemia (similar to diabetes), muscle protein breakdown and lipolysis?
A bodybuilder consumes large amounts of amino acid supplements in the hope that his body will store them and produce increased muscle mass. Why is this likely not to work?