Lab Exam 2 Flashcards
Why is glucose important to the CNS?
Because the central nervous system as well as RBC’s require glucose for their energy needs and without it they die
What is a monosaccharide?
A single unit sugar
What is hexose?
Simple sugars whose molecules contain six carbon atoms
Why is the liver important in reference to glucose?
It synthesizes, stores, converts and releases glucose
What is the excess glucose stored as in the liver?
Glycogen
What organ releases insulin?
The pancreas
What hormones control the concentration of glucose?
Insulin and glucagon; insulin lowers BG levels while glucagon elevates it
How is glucose metabolized?
Via glycolysis followed by the TCA cycle (aka krebs cycle)
How many glucose atoms are produced as a result of glycolysis?
It produces 4 total, but 2 are eliminated, leaving a net gain of 2 glucose atoms
How many ATP atoms are produced at the conclusion of the TCA cycle?
36 ATP for every glucose molecule
What is required for the complete oxidation of glucose?
Because it is an aerobic response, it requires oxygen
What by-products are released by the oxidation of glucose?
- CO2, H2O, ATP, and heat
- The heat produced helps maintain body temperature
What is fermentation of glucose?
Anaerobic metabolism that can produce ATP if the body is experiencing hypoxia
Is fermentation an effective way to produce ATP?
It is less effective than glycolysis because it only produces 4 ATP for every glucose molecule
Where is the highest concentration of glycogen stored?
In the liver, but because muscle tissue has a greater mass, there is more glycogen contained within it
What cells produce, monitor and control glucose?
Beta cells, which are created in the endocrine portion of the pancreas
What cells within the islets of langerhaans produce glucagon?
Alpha cells
What do the delta cells within the pancreatic islets produce?
Somatostatin, which regulates insulin and glucagon
What cell is the only cell in the body that does NOT require insulin to function?
Beta cells
At what concentration would a beta cell be triggered to release insulin?
When the blood glucose concentration exceeds 110 mg/dl
At what concentration is insulin synthesis and concentration inhibited?
When the blood glucose concentration falls between 60 mg/dl
What is euglycemia?
Normal concentration of glucose in the blood
How can euglycemia be maintained?
Exogenously, which is from outside the body, mainly through diet; or endogenously which is inside the body derived from the liver
What is gluconeogenesis?
The creation of more glucose
What hormone is the most dominant when lowering glucose?
Insulin
What hormones may elevate glucose?
Glucagon, epinephrine, growth hormone, and cortisol
What is Diabetes Mellitus?
Results from a decrease in insulin secretion from the beta cells and/or a decrease in insulin action
What is Type I Diabetes?
- Insulin dependent diabetes mellitus
- There is a low amount of insulin in the body and it can’t produce enough to meet the need
What is the most common form of diabetes in dogs and cats?
Type I IDDM
What is the second most common form of diabetes in cats?
Type II NIDDM
What is Type II Diabetes?
- Non-insulin dependent diabetes mellitus
- Spikes in BG levels usually after eating that require insulin which the body can produce
How is type I diabetes managed?
With insulin injections
How is type II diabetes managed?
With dietary therapy and oral hypoglycemic medications
What is Type III Diabetes?
- Impaired glucose tolerance
- Can be caused by hormones or medications
Which type of diabetes can affect pregnant animals?
Type III
What long term medication use can result in type III diabetes?
Corticosteriods
What is thought to be the cause of canine diabetes?
It is considered to be immune mediated in which the body thinks beta cells are foreign and attacks them
What are some other causes of canine diabetes?
Genetic predisposition, chronic pancreatitis, and medication induced
At what percentage of destruction of pancreatic islets do diabetic clinical signs occur?
Progression is slow and 90% of islets are lost before diabetes mellitus occurs
What are the common causes of feline diabetes?
Obesity, pancreatitis, amyloidosis of pancreatic beta cells
What is amyloidosis?
Deposition of material around beta cells which prevents their measurement of glucose
What canine gender is typically afflicted with diabetes?
3x more likely to occur in females
At what age do canines typically become diagnosed with diabetes?
Peak incidence at 7-9 years
What breeds are genetically predisposed to diabetes?
Australian terriers, samoyed, mini and standard schnauzers, mini and toy poodles, pugs, fox terriers, keeshonds, bichon fries, finnish spitz, lhasa apso, cairn terriers
What feline gender is typically affected by diabetes?
Males generally greater than 6 years old
What feline breed is diabetes common in?
None, all can be affected equally
What are the clinical signs of diabetes?
Polyuria, polydipsia polyphagia, weight loss, cataracts in dogs, peripheral neuropathy in cats, plantigrade posture
How can diabetes be diagnosed?
- CBC: red blood cells may be decreased
- Chem panal: hyperglycemia; BG > 200 mg/dl
- UA: glucosuria or ketonuria
What are some goals of diabetes treatment?
- Elimination of clinical signs
- Prevention or slowing or cataract formation and resulting blindness
- Prevention of hypoglycemia or overtreatment
- Prevention and/or treatment of concurrent diseases such as cushing’s, skin infections, or UTI’s
How is diabetes treated?
Dietary management, exercise, insulin injections, or oral hypoglycemic agents
What are some goals of dietary management?
Eliminate obesity and maintain consistency in the timing and caloric content of meals to minimize fluctuations by having slow release of carbohydrates in BG concentrations
What should a diabetic diet contain?
High fiber and low fat, cats should also be fed a high protein, low carb diet and semi moist foods should be avoided
What are some goals of exercise?
To promote fat loss and increase mobilization of insulin from its injection site, but avoid strenuous and sporadic exercise as it can cause severe hypoglycemia
What are the three types of insulin?
- Short acting: emergency use of R insulin
- Intermediate acting: canine use of NPH and Vetsulin
- Long acting: feline use of Lantise and glargine
What are some problems with insulin therapy?
- Rapid insulin metabolism
- Insulin resistance if there is another disease present
- Hypoglycemia aka insulin overdose
- Somogyi phenomenon aka insulin induced hyperglycemia
How can hypoglycemia be treated at home?
If a diabetic animal is exhbiting signs of weakness, shaking, ataxia and seizures, they can be given karo syrup rubbed on the their gums
What is renal disease?
When something is physically wrong with the kidneys, but the function may not be affected
What is renal failure?
When something is functionally wrong with the kidney, at least 75% of total nephron population is non-functional
What happens to the kidneys in renal failure?
The kidneys are no longer able to maintain the regulatory, excretory and endocrine functions required
What happens to hormone production to kidneys in renal failure?
The kidney produces less erythropoietin hormone, which results in anemia especially in cats