Endocrine Control of Fuel Metabolism 1

Question 1

anabolic vs catabolic hormones

Answer 1

anabolic: synthesis of compounds constituting body’s structure, requires ATP (i.e. protein/glycogen synthesis). build fuel stores
hormone ex: insulin, GH, T

catabolic pathways: involve processes that release energy i.e. ox-phos
hormone ex: glucagon, EP, cortisol

Question 2

major pathway carb, lipid, protein metabolism

Answer 2

CARBS: **liver = key site
glucose –> pyruvate (glycolysis)
pyruvate –> acetyl-CoA, enters TCA for oxidation
-excess glucose stored as glycogen in liver/muscle, and then into FA/glycerol and stored as TG

LIPIDS:

• FA –> acetyl-CoA, enters TCA
• excess FA stored as TG in adipose
• stored fat = primary E source in fasting

PROTEINS
-dietary a.a. used for protein synthesis
-excessive a.a. converted to glucose/FA, stored as TG
-in fasting, proteins broken down to a.a., converted to ketones to provide E for brain
= autophagy
- muscle= primary site storage a.a.
v
all eventually make ATP

Question 3

difference btw absorptive and post-absorptive state

Answer 3

absorptive: period after meal that food is digested, nutrients being absorbed
postabsorptive: inter-digestive period that begins 5 h after meal, occurs for 10-14 h

Question 4

source of E during absorptive state

Answer 4

food you are eating

Question 5

source of E during post-absorptive state, prolonged fasting

Answer 5

post: hepatic gluconeogenesis

prolonged fasting: hepatic and renal gluconeogenesis

Question 6

hormonal regulation of Carb metabolism

Answer 6

increase plasma glucose -> release insulin which stimulates glycogen synthesis in liver and glucose uptake from blood-> decrease plasma glucose
Absorptive state

decrease plasma glucose-> promote glucagon release –> stimulates glycogen breakdown in liver–> increase plasma glucose
Postabsorptive state

epinephrine- increases blood glucose (fast)
cortisol- increases blood glucose (slow)
GH- increases blood glucose (slow)

Question 7

endocrine vs exocrine pancreas

Answer 7

exo: secretes bicarbonate and digestive enzymes through duct into intestine
endo: islets of Langerhans,

Question 8

structure/function pancreatic islets

Answer 8

make insulin (beta) and glucagon (alpha) and somatostatin and PP
- innervated by SNS and PSNS