PNB 2274 Exam 4| QUESTIONS WITH COMPLETE SOLUTIONS 100% VERIFIED| LATEST UPDATE
GRADED A+
What is steroid-genesis? - the production of steroids from cholesterol
- modified by addition of OH and double bonded O
- cytochrome P450s cleave O2 into a single O
- cholesterol side chain cleavage is rate limiting step
- steroidogenesis is under the regulation of ACTH and cAMP
- immediate, later, and long term (trophic) effects
What is the effect of the mineralocorticoid aldosterone? - up-regulates expression of
Na+/K+-ATPase leading to increased numbers of Na+ pumps in the basolateral membrane of
tubular epithelial cells
- up-regulates expression of Na+ channel that facilitates uptake of sodium form tubular lumen
- increased sodium resorption and decreased sodium loss
- increased renal H2O absorption
- increased renal K+ secretion
- leads to an increase in blood fluid and pressure
What are the effects of the glucocorticoids cortisol/corticosterone? - hyperglycemia
(increased glycogenolysis and gluconeogenesis)
- immunosuppression (prednisone)
- increased lipolysis
- decreased cellular uptake of AA/glucose
- increased protein degradation
- increased cell growth, differentiation, development (lung fetal development)
,What is Cushing's syndrome? - hyper cortisol secretion
- adrenal tumor or over medication
- symptoms: hypertension, round red face, weak muscles, weak bones, acne, amenorrhea
- possible over-secretion of ACTH
What are androgens? - androstenediol and DHEA
- converted to testosterone in testes and estrogen in ovaries
- have bone protective effects and increase immunity, working against the effects of cortisol
- androgens directly affect the CNS
Progesterone follows what type of pathway and what would be the reverse of this? - classic
pathway: binding to nuclear receptor resulting in gene transcription
- non-classic pathway: through GPCRs; membrane associated receptors, intracellular growth
factors, c-SRC/MAPK pathway; integration of endocrine and mechanical signals
Where is adipose tissues found? subcutaneously (beneath skin)
visceral (around internal organs)
in bone marrow
muscle tissue
breast tissue
What hormones are released by adipocytes? What are their effects? leptin, adiponectin and
resistin
- influence energy metabolism, appetite, cytokine like factors
How does the hormone leptin function? - in response to FFA levels within adipocytes
,- when the FFA levels increase in adipocytes, leptin is released and sent to hypothalamus target
cells where it has an effect on appetite
- a satiety hormone
- the obese mouse did not have properly functioning leptin
Can leptin be used in humans to treat obesity/type 2 diabetes? NO: leptin does not affect
appetite in humans
- it is the absence of leptin that is the signal to eat
- when you lose weight leptin decreasing
What is the function of the adiponectin hormone?
What effect does it have on insulin? - protein hormone
- released in response to blood glucose and FFAs
- Adiponectin and leptin reverse insulin resistance in mice
- anti-diabetic, anti-inflammatory, anti-atherogenic, and cardioprotective
What is unique about the GPCR for adiponectin? GPCR receptor has C-terminus external and
N-terminus internal
- home and heterodimering receptors
What is the function of resistin hormone? - associated with obesity
- thought to increase insulin resistance
- induces inflammation
- cytokine
Explain what cytokines are: - produced from adipose as well as a range of cells (immune,
epithelial and adipose)
, - not a classic hormone: affects local environment and distal environment; inflammation and
pyrogens
What is the function of the orexin hormone? - regulates arousal, wakefulness and appetite
- lack of orexin hormones causes narcolepsy and obesity because it effects brown adipose
tissue
- an orexic agent is anandamide
What are the two types of functions of the pancreas? - Exocrine: secretion of alkali buffers,
salts and enzymes into duodenum
- Endocrine: secretion of insulin and glucagon via Islets of Lagerhan
(pancreas is found beneath stomach)
What are the 5 cell types found within the islet of Langerhans and their respective secretions?
- alpha cells : secrete glucagon
- beta cells: secrete insulin and amylin (slows gastric emptying and induces satiety); 75%
- Scells: secrete somatostatin (GH inhibiting hormone)
- PP cells: pancreas polypeptide (stimulates pancreatic secretions into the duodenum)
- Ecells: secrete ghrelin (stimulates stomach secretions, motility)
By the 1600s, physicians knew these 3 symptoms associated with diabetes: - polydipsia
(excessive thirst)
- polyphagia (excessive hunger)
- polyuria (excessive urination)
We learned in 1869 that what structure is damaged in diabetics: - Islets of Lagerhands in the
pancreas
GRADED A+
What is steroid-genesis? - the production of steroids from cholesterol
- modified by addition of OH and double bonded O
- cytochrome P450s cleave O2 into a single O
- cholesterol side chain cleavage is rate limiting step
- steroidogenesis is under the regulation of ACTH and cAMP
- immediate, later, and long term (trophic) effects
What is the effect of the mineralocorticoid aldosterone? - up-regulates expression of
Na+/K+-ATPase leading to increased numbers of Na+ pumps in the basolateral membrane of
tubular epithelial cells
- up-regulates expression of Na+ channel that facilitates uptake of sodium form tubular lumen
- increased sodium resorption and decreased sodium loss
- increased renal H2O absorption
- increased renal K+ secretion
- leads to an increase in blood fluid and pressure
What are the effects of the glucocorticoids cortisol/corticosterone? - hyperglycemia
(increased glycogenolysis and gluconeogenesis)
- immunosuppression (prednisone)
- increased lipolysis
- decreased cellular uptake of AA/glucose
- increased protein degradation
- increased cell growth, differentiation, development (lung fetal development)
,What is Cushing's syndrome? - hyper cortisol secretion
- adrenal tumor or over medication
- symptoms: hypertension, round red face, weak muscles, weak bones, acne, amenorrhea
- possible over-secretion of ACTH
What are androgens? - androstenediol and DHEA
- converted to testosterone in testes and estrogen in ovaries
- have bone protective effects and increase immunity, working against the effects of cortisol
- androgens directly affect the CNS
Progesterone follows what type of pathway and what would be the reverse of this? - classic
pathway: binding to nuclear receptor resulting in gene transcription
- non-classic pathway: through GPCRs; membrane associated receptors, intracellular growth
factors, c-SRC/MAPK pathway; integration of endocrine and mechanical signals
Where is adipose tissues found? subcutaneously (beneath skin)
visceral (around internal organs)
in bone marrow
muscle tissue
breast tissue
What hormones are released by adipocytes? What are their effects? leptin, adiponectin and
resistin
- influence energy metabolism, appetite, cytokine like factors
How does the hormone leptin function? - in response to FFA levels within adipocytes
,- when the FFA levels increase in adipocytes, leptin is released and sent to hypothalamus target
cells where it has an effect on appetite
- a satiety hormone
- the obese mouse did not have properly functioning leptin
Can leptin be used in humans to treat obesity/type 2 diabetes? NO: leptin does not affect
appetite in humans
- it is the absence of leptin that is the signal to eat
- when you lose weight leptin decreasing
What is the function of the adiponectin hormone?
What effect does it have on insulin? - protein hormone
- released in response to blood glucose and FFAs
- Adiponectin and leptin reverse insulin resistance in mice
- anti-diabetic, anti-inflammatory, anti-atherogenic, and cardioprotective
What is unique about the GPCR for adiponectin? GPCR receptor has C-terminus external and
N-terminus internal
- home and heterodimering receptors
What is the function of resistin hormone? - associated with obesity
- thought to increase insulin resistance
- induces inflammation
- cytokine
Explain what cytokines are: - produced from adipose as well as a range of cells (immune,
epithelial and adipose)
, - not a classic hormone: affects local environment and distal environment; inflammation and
pyrogens
What is the function of the orexin hormone? - regulates arousal, wakefulness and appetite
- lack of orexin hormones causes narcolepsy and obesity because it effects brown adipose
tissue
- an orexic agent is anandamide
What are the two types of functions of the pancreas? - Exocrine: secretion of alkali buffers,
salts and enzymes into duodenum
- Endocrine: secretion of insulin and glucagon via Islets of Lagerhan
(pancreas is found beneath stomach)
What are the 5 cell types found within the islet of Langerhans and their respective secretions?
- alpha cells : secrete glucagon
- beta cells: secrete insulin and amylin (slows gastric emptying and induces satiety); 75%
- Scells: secrete somatostatin (GH inhibiting hormone)
- PP cells: pancreas polypeptide (stimulates pancreatic secretions into the duodenum)
- Ecells: secrete ghrelin (stimulates stomach secretions, motility)
By the 1600s, physicians knew these 3 symptoms associated with diabetes: - polydipsia
(excessive thirst)
- polyphagia (excessive hunger)
- polyuria (excessive urination)
We learned in 1869 that what structure is damaged in diabetics: - Islets of Lagerhands in the
pancreas
