Term
| Describe the 2 portions of the pancreas and list the functions of each |
|
Definition
Pancreas is actually 2 organs, 1 exocrine and 1 endocrine, held together in one stroma. The
Endocrine pancreas – secretes hormones involved in blood sugar regulation, such as insulin and glucagons
Exocrine pancreas – produces enzymes we use to digest our food. The 3 primary pancreatic enzymes are trypsin, amylase (to digest starches) and lipase (to take fats). Released into the lumen of other organs through a duct system
Enzymes are stored in inactive forms inside special granules in the exocrine pancreatic tissue (the “acinar cells”) and are secreted into the duodenum (the first part of the small intestine after the stomach) when ground up food begins its passage out of the stomach. Once nutrients are broken down into smaller molecules (i.e. they are digested), they can be absorbed down the entire length of the GI tract. Without adequate productive of these enzymes, we cannot break down/digest our food. If we cannot digest the food, we cannot absorb the food. We get skinny, have especially nasty rather greasy diarrhea, or both. Often, a dog will develop a dry, dandruffy coat from inability to absorb dietary fats. |
|
|
Term
|
Definition
| secretes hormones involved in blood sugar regulation, such as insulin and glucagons |
|
|
Term
|
Definition
produces enzymes we use to digest our food. The 3 primary pancreatic enzymes are trypsin (and proteases to digest protein), amylase (to digest starches) and lipase (to take fats). Released into the lumen of other organs through a duct system
Enzymes are stored in inactive forms inside special granules in the exocrine pancreatic tissue (the “acinar cells”) and are secreted into the duodenum (the first part of the small intestine after the stomach) when ground up food begins its passage out of the stomach. Once nutrients are broken down into smaller molecules (i.e. they are digested), they can be absorbed down the entire length of the GI tract. Without adequate productive of these enzymes, we cannot break down/digest our food. If we cannot digest the food, we cannot absorb the food. We get skinny, have especially nasty rather greasy diarrhea, or both. Often, a dog will develop a dry, dandruffy coat from inability to absorb dietary fats. |
|
|
Term
| What tests are used to help evaluate the pancreas? |
|
Definition
Exocrine Pancreas Tests
Commonly performed
- Amylase
- Lipase
Also available:
- Trypsinlike immunoreactivity
- Serum pancreatic lipase immunoreactivity
In cats, serum amylase and serum lipase activities have been shown to have limited clinical significance in the dx of pancreatitis. In exp induced pancreatitis in cats, serum amylase actually decrease. Serum activities of both enzymes are frequently normal in cats w/ pancreatitis
- Glucose
- Fructosamine
- Glycosylated hemoglobin
- B-Hydroxybutrate
- Glucose tolerance
- Insulin tolerance
- Glucagon tolerance |
|
|
Term
|
Definition
- Glucose
- Fructosamine
- Glycosylated hemoglobin
- B-Hydroxybutrate
- Glucose tolerance
- Insulin tolerance
- Glucagon tolerance |
|
|
Term
|
Definition
Exocrine Pancreatic Insufficiency
Without adequate productive of these enzymes, we cannot break down/digest our food. If we cannot digest the food, we cannot absorb the food. We get skinny, have especially nasty rather greasy diarrhea, or both. Often, a dog will develop a dry, dandruffy coat from inability to absorb dietary fats.
Enzymes are stored in inactive forms inside special granules in the exocrine pancreatic tissue (the “acinar cells”) and are secreted into the duodenum (the first part of the small intestine after the stomach) when ground up food begins its passage out of the stomach. Once nutrients are broken down into smaller molecules (i.e. they are digested), they can be absorbed down the entire length of the GI tract. |
|
|
Term
|
Definition
| presence of excess lipids in the blood |
|
|
Term
| What is the most accurate test of pancreatic digestive function? |
|
Definition
| Serum Trypsin-like Immunoreactivity test |
|
|
Term
| .Of the 3 pancreatic enzymes, which most accurately determines functioning of the exocrine pancreas? |
|
Definition
|
|
Term
| Are amylase and lipase levels directly proportional to the severity of pancreatitis? |
|
Definition
| The degree of lipase/amylase activity is not directly proportional to the severity of pancreatitis |
|
|
Term
| . Which test would be most useful to diagnose EPI? |
|
Definition
Serum Trypsin-like Immunoreactivity test
looks for a normal level of trypsin-like enzymes in the bloodstream |
|
|
Term
| What tests evaluate the endocrine functions of the pancreas? |
|
Definition
- Glucose
- Fructosamine
- Glycosylated hemoglobin
- B-Hydroxybutrate
- Glucose tolerance
- Insulin tolerance
- Glucagon tolerance |
|
|
Term
| What substance is produced and released by the pancreatic islets and what is its function? |
|
Definition
The pancreatic islets have 3 main endocrine cell types
- alpha cells – glucagon – effect opposite to insulin. Raises the BG level through 2 main mechanisms. Because other hormones such as GH and glucocorticoid hormones (from the adrenal cortex) have similar hyperglycemic effects, a deficiency of glucagons is not as devastating to the body as a deficiency of insulin
2 main mechanisms of raising BG
> stimulates liver cells to convert glycogen (a storage form of glucose) to glucose
> stimulates gluconeogenesis (the conversion of fat and protein breakdown products to glucose)
- beta cells – insulin – causes glucose, amino acids, and fatty acids in the bloodstream to be absorbed through cell membranes into body cells and used for energy. Acts to lower the level of glucose in the blood
- delta cells – somatostatin - |
|
|
Term
| Why is it so important to quickly separate the serum or plasma from the erythrocytes when running a glucose test? |
|
Definition
- Glucose levels may drop 10% an hour if the sample of plasma is left in contact with erythrocytes at room temp.
- This is due to in vitro glycolysis by the blood cells – mature erythrocytes use glucose for energy.
- Even the use of a SST may not prevent this.
- If sample orig had a normal BG level, erythrocytes may use enough glucose to decrease the level to below normal or to zero
- If plasma cannot be removed immed, the anticoagulant of choice is sodium fluoride at 6 – 10 mg/ml of blood
- Sodium fluoride may be used as a glucose preservative with EDTA at 2.5 mg/ml of blood
- Refrigeration slows glucose utilization by erythrocytes |
|
|
Term
| . What effects does a recent meal or stress have on the blood glucose level? |
|
Definition
|
|
Term
| What is the disease that causes a persistently elevated blood glucose level |
|
Definition
|
|
Term
| What is the major adrenal hormone in animals? |
|
Definition
|
|
Term
| Define Addison’s disease. List the causes and the clinical signs. |
|
Definition
Hypoadrenocorticism – caused by a deficiency of adrenocortical hormones, usually a progressive condition that can lead to circulatory problems and kidney failure. Effects of the dz can be mimicked if long-term corticosteroid drug admin is suddenly stopped (iatrogenic hypoadrenocorticism)
Clinical signs:
- Somewhat nonspecific
- Weakness
- Lethargy
- Vomiting
- diarrhea |
|
|
Term
| Define Cushing’s syndrome. List the causes and the clinical signs. |
|
Definition
Hyperadrenocorticism – caused by too much glucocorticoid hormone being produced by the adrenal cortex. Signs of naturally occurring hyperadrenocorticism can be mimicked by admin of high doses of glucocorticoid drugs (iatrogenic Cushing’s)
Initial clinical signs:
- PU/PD
- Polyphagia (increased appetite)
Long term signs:
- Hair loss
- Muscle wasting
- Slow wound healing |
|
|
Term
| List the tests used to study the adrenal gland and what each is used for. |
|
Definition
- ACTH stimulation test – to test for suspected hyper- or hypo-adrenocorticism
- Dexamethasone suppression test – evaluates the adrenal glands differently by using the adrenal feedback loops.
> The low-dosage test confirms or replaces the ACTH response test for hyperadrenocorticism (Cushing’s)
> the high-dosage test goes further, differentiating pituitary from adrenal causes of hyperadrenocorticism. In cats, only a high-dose suppression test is suitable
- Corticotrophin-releasing hormone stimulation – may be indicated to differentiate between pituitary-dependent and primary hyperadrenocorticism |
|
|
Term
| What is the most commonly used and most accurate test to analyze the adrenal glands? |
|
Definition
- ACTH stimulation test
- more than 80% accurate in diagnosing adrenocortical hyperfunction in the dog
- more than 50% accurate in diagnosing adrenocortical hyperfunction in the cat |
|
|
Term
| List the functions of thyroid hormone |
|
Definition
| - Influences metabolic rate, growth and differentiation of all body cells |
|
|
Term
| List the clinical signs of Hypothyroidism |
|
Definition
Mental dullness
Lethargy; listlessness
Exercise intolerance
Reluctance to engage in normal activities
Intolerance to cold (“heat-seeking” behavior)
Weight gain, without increased appetite or food consumption
Symmetrical hair loss (alopecia), without itchiness (bilaterally symmetric, nonpruitic truncal alopecia; the head and legs are often spared)
Excessive shedding
Greasy skin; flaky skin (seborrhea)
Dandruff
Pimples or other pustules on the skin (pyoderma)
Chronic ear infections (otitis)
Dry, brittle hair coat
Skin thickening, especially on the face and forehead (myxedema), giving a puffy appearance referred to as a “tragic facial expression”
The dog’s neuromuscular, reproductive, cardiovascular and/or gastrointestinal systems may be affected as well, causing one or more of the following symptoms:
Slow heart rate (bradycardia)
Constipation
Diarrhea
Incoordination (ataxia)
Seizures
Heart arrhythmias (irregular heart rhythms)
Anemia
Infertility
Decreased libido (reduced sex drive)
Abortion
Testicular atrophy |
|
|
Term
| Clinical signs of Hyperthyroidism |
|
Definition
weight loss,
increased appetite (although some patients have decreased appetite),
vomiting,
increased thirst and urination,
hyperactivity
diarrhea.
The high levels of thyroid hormones can cause the development of heart disease, and these patients may have a heart murmur, difficulty breathing, high heart rate and arrhythmias |
|
|
Term
| What tests are used to diagnose thyroid disease? |
|
Definition
- TSH (Thyroid-stimulating hormone) response
- Thyrotropin-releasing hormone (TRH) response
- Triiodothyronine suppression test |
|
|
Term
| Define electrolytes and their functions |
|
Definition
The negative ions, or anions, and positive ions, or cations, of elements found in all body fluids of all organisms.
Some fxns of electrolytes are maintenance of:
- Water balance
- Fluid osmotic pressure
- Normal muscular and nervous functions
- Maint and activation of several enzyme systems and in acid-base regulation |
|
|
Term
| list the 7 most commonly measured electrolytes |
|
Definition
Major electrolytes in plasma (7 most commonly measured ones):
- Calcium
- Inorganic phosphorus
- Magnesium
- Sodium
- Potassium
- Chloride
- bicarbonate |
|
|
Term
| sources and functions of calcium |
|
Definition
Calcium – more than 99% is found in bones. Remaining 1% or less in whole blood (plasma or serum) has major fxns in the body, incl
- Maintenance of neuromuscular excitability and tone (decreased calcium can result in muscular tetany)
- Maint of activity of many enzymes
- Facilitation of blood coagulation
- Maint of inorganic ion transfer across cell membranes |
|
|
Term
|
Definition
more than 80% found in bones, remaining 20% or less found in plasma and serum . The phosphorus in whole blood mostly w/in the erythrocytes is organic phosphorus.
Major fxns:
- Energy storage, release and transfer
- Involvement in carb metabolism
- Composition of many physiologically important substances, such as neucleic acids and phospholipids |
|
|
Term
|
Definition
- major cation of plasma and interstitial, or extracellular, fluid
- plays important role in water distribution and bldy fluid osmotic pressure maintenance
- in kidney – sodium filtered through glomeruli and resorbed back into the body through the tubules in exchange, as needed, for hydrogen ions
- in this way, sodium plays vital role in pH regulation of urine and acid-base balance
- hypernatremia – elevated blood level of sodium
- hyponatremia - decreased blood level of sodium |
|
|
Term
|
Definition
- predominant extracellular anion
- important role in maint of water distribution, osmotic pressure, and the normal anion/cation ratio
- usually incl in electrolyte profiles due to its close relationship to sodium and bicarbonate levels
- hyperchloremia – elevated blood chloride levels
- hypochloremia – decreased blood chloride levels
- hemolysis may affect test results by diluting sample w/ erythrocyte fluid
- prolonged storage w/o first separating out the blood cells may cause slightly low results |
|
|
Term
|
Definition
- 2nd most common anion of plasma
- important part of the bicarbonate/carbonic acid buffer system
- aids in transport of carbon dioxide from the tissues to the lungs
- these fxns help keep the body pH in balance as acids and bases are continuously introduced into the body
- kidney regulates bicarbonate levels in the body by excreting excesses after it has resorbed all that is needed
- bicarbonate levels frequently estimated from blood carbon dioxide levels
- total bicarbonate level is approx 95% of the total CO2 measured
- arterial blood is sample of choice
- if plasma used, lithium heparinate is the anticoagulant of choice
- sample should be chilled in ice water to prevent glycolysis from altering the acid-base composition
- freezing the sample results in hemolysis
- most test methods require incubation at 37 C |
|
|
Term
|
Definition
- major intracellular cation
- important for normal muscular fxn, respiration, cardiac fxn, nerve impulse transmission, and carbohydrate metabolism
- in acidotic animals, K ions leave the intracellular fluid as they are replaced by hydrogen ions, resulting in hyperkalemia
- hyperkalemia – elevated plasma K levels
- plasma is preferred sample to test as platelets may release K during the clotting process, causing artificially elevated K levels
- hemolysis should be avoided – concentration of K w/in eryth is higher than conc in plasma. Hemolysis releases K into plasma, resulting in artificially elevated K levels
- do not refrigerate until plasma has been separated from cells because cooler temps promote loss of K from the cells w/o evidence of hemolysis
- don’t freeze until plasma has been separated from cells because the resulting hemolysis makes the sample unusable |
|
|
Term
|
Definition
- cation
- 4th most common cation in the body, 2nd most common intracellular cation
- found in all body tissues
- more than 50% found in bones
- activates enzyme systems and is involved in production and decomposition of acetylcholine
- cattle/sheep are the only domestic animals that show clinical signs related to magnesium deficiencies |
|
|
Term
|
Definition
– more than 80% found in bones, remaining 20% or less found in plasma and serum . The phosphorus in whole blood mostly w/in the erythrocytes is organic phosphorus.
Major fxns:
- Energy storage, release and transfer
- Involvement in carb metabolism
- Composition of many physiologically important substances, such as neucleic acids and phospholipids |
|
|
Term
|
Definition
more than 99% is found in bones. Remaining 1% or less in whole blood (plasma or serum) has major fxns in the body, incl
- Maintenance of neuromuscular excitability and tone (decreased calcium can result in muscular tetany)
- Maint of activity of many enzymes
- Facilitation of blood coagulation
- Maint of inorganic ion transfer across cell membranes
Samples for calcium testing should not be collected using EDTA or oxalate or citrate anticoagulants because they bind with calcium and make it unavailable for assay |
|
|
Term
| Why should samples for calcium testing NOT be collected using EDTA or oxalate anticoagulants? |
|
Definition
| Samples for calcium testing should not be collected using EDTA or oxalate or citrate anticoagulants because they bind with calcium and make it unavailable for assay |
|
|
Term
|
Definition
| - hypernatremia – elevated blood level of sodium |
|
|
