Glucose Regulation - PowerPoint PPT Presentation

Loading...

PPT – Glucose Regulation PowerPoint presentation | free to download - id: cfa07-ZDc1Z



Loading


The Adobe Flash plugin is needed to view this content

Get the plugin now

View by Category
About This Presentation
Title:

Glucose Regulation

Description:

Glucose Regulation. What is diabetes? Cells need sugar ATP and the Krebs Cycle ... Almost everything we eat can be converted and used by Kreb's cycle ... – PowerPoint PPT presentation

Number of Views:216
Avg rating:3.0/5.0
Slides: 28
Provided by: facult6
Learn more at: http://faculty.ccri.edu
Category:

less

Write a Comment
User Comments (0)
Transcript and Presenter's Notes

Title: Glucose Regulation


1
Glucose Regulation
  • What is diabetes?
  • Cells need sugarATP and the Krebs Cycle
  • What comes in through the gutbasic nutrition
  • Role of liver in processing nutrients, storing
    glucose
  • Absorptive Pathways and role of insulin from
    pancreas
  • Post-absorptive Pathways
  • Understanding Diabetes

2
Diabetes mellitusstarvation amidst plenty
  • Type I
  • Juvenile onset
  • Pancreas beta cells die, no insulin produced
  • Type II
  • Adult onset
  • Complicated set of factors, some insulin
    production
  • Goalunderstand why we need insulin

3
Cells and Glucose
  • All cells of body need constant glucose supply,
    especially nervous tissue
  • Most other nutrients can be converted into
    glucose or derivatives for making ATP
  • ATP is celluar gasoline

4
Glycolysis and Krebs Cycle
  • Main way that cells make ATP
  • Glucose is principle reactant

5
(No Transcript)
6
(No Transcript)
7
Why not eat just sugar?
8
Essential Amino Acids
  • Only additional nutrients that body cant produce
  • Needed for making proteins
  • Also some vitamins and minerals must come from
    diet

9
What happens to the rest of what we eat?
10
Interconversion of Nutrients
  • Almost everything we eat can be converted and
    used by Krebs cycle

11
Why not eat just sugar?
  • We need some other nutrientsessential amino
    acids, vitamins, minerals
  • Our body also uses fats and proteins directly
    from diet

12
What keeps sugar constantly available in blood?
  • Immediately after a meal, nutrients are flowing
    into blood across wall of stomach, small
    intestines
  • Between meals, when food has mostly been
    digested, nutrients are not available
  • Nonetheless, blood sugar levels are kept
    virtually constant
  • How is this possible?
  • Role of liver in temporary storage of glucose as
    glycogen
  • Differences in absorptive and post-absorptive
    metabolic pathways

13
Liver
  • STRUCTURE
  • Large ventral organ of abdominal cavity with
    multiple lobes (learn them!!)
  • Sets against inferior surface of diaphragm on
    left side
  • Forms as outpocketing of gut--common bile duct is
    left as connection
  • Bile duct is two-way street (bile from hepatic
    duct is stored in gall bladder and later expelled
    to common bile duct to duodenum)
  • FUNCTION
  • Digestion--bile is digestive enzymes plus RBC
    breakdown product
  • Removes nutrients and toxins from blood (hepatic
    portal system brings gut blood directly to liver)
  • Glucose metabolism (with pancreas--see below)

14
General blood supply to gut--ventral branches off
of aorta
  • Celiac a.--to stomach, liver, pancreas, spleen,
    duodenum
  • Superior (cranial mesenteric a.--to small
    intestines and most of colon
  • Inferior (caudal) mesenteric a.--to descending
    colon, rectum

15
Liver Blood Supply
  • Hepatic Vein
  • from inferior vena cava
  • Hepatic Artery
  • from abdominal aorta
  • Hepatic Portal Vein
  • Carries nutrient-rich blood from stomach
    intestines to liver
  • Portal system 2 capillary beds!

pg 660
16
Hepatic Portal System--anatomy
17
Hepatic Portal System--concept
Fig. 19.22, MM
  • Directs blood that has already been through gut
    capillaries into liver capillaries (or sinusoids)
  • Allows nutrients and toxins to be removed from
    blood

18
How does liver work?
  • Blood from portal vein and hepatic artery enter
    into central vein of liver lobules
  • Leaky capillaries called sinusoids then bring
    blood into contact with hepatocytes or liver cells

19
Liver function
  • Versatile hepatocytes do the following
  • Process nutrients including storage of glucose
  • Store fat-soluble vitamins for later use by body
  • Detoxification of blood
  • Other macrophage-like Kupffer cells also remove
    debris such as worn-out RBCs

20
Following a meal, with nutrients flowing into
blood from gut
21
Role of insulin in take-up of glucose (from
pancreas beta cells) by cells during absorptive
state
22
Between meals, with no nutrients flowing into
blood from gut
23
  • Role of glucagon (from pancreas alpha cells) in
    release of glucose by cells during
    post-absorptive state

24
Pancreas
  • STRUCTURE
  • Smaller, diffuse gland
  • Head in C of duodenum
  • Tail extends towards spleen
  • FUNCTION
  • Digestion--produces most digestive enzymes
  • Glucose metabolism--Islets of Langerhans
  • Beta cells make insulin
  • Alpha cells make glucagon

25
How Stuff Works Diabetes http//www.howstuffwo
rks.com/diabetes1.htm
26
Glucose metabolism
  • Liver receives blood from intestines (dont
    forget hepatic portal system
  • After meal, in response to insulin from pancreas,
    glucose stored as complex carbohydrate--glycogen--
    in liver
  • Between meals, in response to glucagon from
    pancreas, glucose is released
  • Pancreas releases insulin when sugar levels in
    blood go up
  • Inadequate or zero insulin production results in
    hyperglycemia or high blood sugar
  • Overproduction or over-dosing of insulin results
    in hypoglycemia or low blood sugar--insulin shock
  • Diabetes is insufficient production of insulin
  • Type I--juvenile onset with elimination of Islets
    of langerhans and zero insulin production
  • Type II--adult onset with gradual loss of insulin
    production

27
(No Transcript)
About PowerShow.com