Exam 3: Endocrine Principles Flashcards
What are ion-channel-linked receptors used by?
Neurotransmitters
What are G protein-linked hormone receptors coupled with?
Heterotrimeric GTP-binding proteins
T/F: Enzyme-linked hormone receptors are single-pass transmembrane receptors.
True
What is an example of an enzyme-linked hormone receptor?
Leptin receptor of JAK-STAT
Polypeptide and protein hormones are kept, where, until needed?
Secretory vesicles
What are polypeptide and protein hormones synthesized as?
Preprohormones
Which hormone is lipid soluble & diffuses readily across cell membranes?
Steroids
How are steroids stored?
Large quantities of cholesterol esters
What are amine hormones derived from?
Tyrosine
What hormones are formed by enzymes in cytoplasmic compartments of glandular cells?
Amine hormones
What hormones are formed in the adrenal medulla & stored in vesicles until needed?
Catecholamines (epinephrine & norepinephrine)
What protein stimulates the adenyl cyclase-cAMP system?
Gs
What does adenyl cyclase catalyze?
ATP–>cAMP
What protein reduces the formation of ATP via the adenyl cyclase-cAMP system?
Gi
What mobilizes calcium ions from mitochondria & ER?
IP3
What activates protein kinase C & has an arachidonic acid component?
DAG
What fills calmodulin and what does calmodulin initiate?
Calcium.
Activation/Inhibition of protein kinases
Which hormones act directly on DNA?
Steroids & thyroid hormones
T/F: Steroids, acting directly on DNA, is quicker than membrane-receptor mediated signaling.
False, it is slower
How long do thyroid hormones stay bound to DNA?
days to weeks
What is the anterior pituitary derived from?
Roof of the mouth
What are the five cell types that can be differentiated in the anterior pituitary?
Somatotropes. Corticotropes. Thyrotropes. Gonadotropes. Lactotropes
What do somatotropes secrete?
HGF
What do corticotropes secrete?
ACTH
What do Thyrotropes secrete?
TSH
What do gonadotropes secrete?
LH & FSH
What do lactotropes secrete?
Prolactin
Where is ADH formed in the posterior pituitary?
Supraoptic nuclei
Where is oxytocin formed in the posterior pituitary?
Paraventricular nuclei
What controls the anterior pituitary?
Hypothalamus
Where are hormones of the hypothalamus secreted into?
Median eminence
Protein synthesis, fatty acid mobilization, decreasing glucose utilization, & liver formation of somatomedins are all functions of what?
Growth hormone
Which somatomedin is the most important and what is the other name for it?
Somatomedin C (IGF-1)
