UNITIII Ketosis Ketosis Ketosis simply means that ketones

UNITIII Ketosis

Ketosis �Ketosis simply means that ketones are present in body fluids in elevated concentrations �Ketone bodies are acetoacetic hydroxybutyric acid and acetone acid, beta- �Ketosis is frequently associated with ketoacidosis �Ketosis is a normal response to low glucose availability �Ketogenesis take pace in lever �Aetyl Co. A is precursor of ketone bodies

Mechanism of development �Occurs during fasting, starvation, restriction, prolonged exercise carbohydrate �Trace levels of ketones are always present in the blood �Increase when blood glucose reserves are low �Liver shifts from primarily metabolizing carbohydrates to metabolizing fatty acids

Mechanism of development…. . �When the liver rapidly metabolizes fatty acids into acetyl-Co. A, some acetyl-Co. A molecules can then be converted into ketone bodies �These ketone bodies can function as an energy source �The liver itself cannot utilize these molecules for energy, so the ketone bodies are released into the blood for use by peripheral tissues including the brain �Acetyl-Co. A can be metabolized through the TCA cycle in any cell

Mechanism of development…. . �It can also undergo ketogenesis in the mitochondria of liver cells �When glucose availability is low, oxaloacetate is diverted away from the TCA cycle and is instead used to produce glucose via gluconeogenesis �Excess of Acetyl-Co. A synthesize ketone bodies �Uncontrolled production of ketones leads to keosis

Biochemical alteration �Ketonemia- the presence of an abnormally high concentration of ketone bodies in the blood �Hypoglycemia- decrease in blood glucose level �Ketonuria- presence of ketone bodies in urine �Rothera's test- Detection of ketone bodies in urine

Types of ketosis �Alimentary ketosis �Fasting Ketosis �Diabetic Ketosis �Ketosis Associated with Pregnancy and Lactation Bovine ketosis- Cattle Pregnancy toxemia- Sheep �Postexercise Ketosis

Alimentary ketosis �Alimentary ketosis occurs when cattle have been fed spoiled silage that contains excessive amounts of butyric acid �Ketogenesis can occur from Volatie Fatty acid �Propionate is the major gluconeogenic precursor and is not an important precursor of ketones �Butyrate is converted to 3 -hydroxybutyrate by the rumen epithelium �Rumen epithelial cells possess high activities of butyryl. Co. A synthetase, which can convert butyrate to butyryl. Co. A

Fasting Ketosis �During fasting, hormonal changes occur that promote lipolysis �Plasma glucose (hypoglycemia) concentrations will decrease �Low plasma insulin concentrations high plasma glucagon concentrations �These hormonal changes will increase c. AMP concentrations in adipose cells, which leads to the activation of hormone sensitive lipase �Long chain fatty acid released from adipose tissue

Diabetic Ketosis �More frequently in dogs and cats than other domestic species � Diabetes is accompanied by hyperglycemia, whereas most other ketotic syndromes occurring in domestic animals are usually accompanied by normoglycemia or hypoglycemia �The ketonemia in diabetes is due to increased lipolysis in adipose plus accelerated hepatic gluconeogenesis

Post exercise ketosis �During exercise long chain fatty acid bodies is utilized by muscles �Ketone bodies formed from long chain fatty acid is utilized by muscle �Trained athlete have high activity of enzyme related to fatty acid and ketone bodies utilization �After exercise ketone bodies is still synthesizing which leads to accumulation of ketone bodies (Ketosis)