1. METABOLISM PART2

2. The Liver and Gallbladder
3. Liver
The largest glandular organ in the body
Weight: 1.5 kg
Reddish brown and has four unequal lobes
Supplying vessels: 1. hepatic and portal vein
Location: right upper quadrant, below the diaphragm
the only internal human organ capable of natural regeneration of lost tissue
4. Functions:
Gluconeogenesis the synthesis of glucose from certain amino acids, lactate or glycerol
Glycogenolysis the breakdown of glycogen into glucose
Glycogenesis the formation of glycogen from glucose
Protein metabolism
Lipid metabolism: Cholesterol synthesis
Lipogenesis, the production of triglycerides (fats).
5. The liver produces coagulation factors
. The liver produces and excretes bile
The liver also produces insulin-like growth factor 1 (IGF-1), a polypeptide protein hormone that plays an important role in childhood growth and continues to have anabolic effects in adults.
The liver is a major site of thrombopoietinproduction,a glycoprotein hormone that regulates the production of platelets by the bone marrow.
6. The breakdown of insulin and other hormones
The liver breaks down hemoglobin, creating metabolites that are added to bile as pigment (bilirubin and biliverdin).
The liver breaks down or modifies toxic substances , methylation and most medicinal products in a process called drug metabolism. This sometimes results in toxication, when the metabolite is more toxic than its precursor.
The liver converts ammonia to urea.
7. The liver stores a multitude of substances, including glucose
The liver is responsible for immunological effects- the reticuloendothelial system of the liver contains many immunologically active cells, acting as a 'sieve' for antigens carried to it via the portal system.
The liver produces albumin, the major osmolar component of blood serum
The liver synthesizes angiotensinogen a hormone that is responsible for raising the blood pressure when activated by renin, an enzyme that is released when the kidney senses low blood pressure.
8. Liver functions
include liver enzymes, are groups of clinical biochemistry laboratory blood assays designed to give information about the state of a patient's liver.
9. Albumin is a protein made specifically by the liver, and can be measured cheaply and easily. It is the main constituent of total protein; the remaining fraction is called globulin .
The half-life of albumin is approximately 20 days.
Albumin is not considered to be an especially useful marker of liver synthetic function; coagulation factors
10. Alaninetransaminase (ALT), also called Serum GlutamicPyruvateTransaminase (SGPT) or Alanineaminotransferase (ALT) is an enzyme present in hepatocytes (liver cells).
Aspartatetransaminase (AST) Aspartatetransaminase (AST) also called Serum GlutamicOxaloaceticTransaminase (SGOT) or aspartateaminotransferase (ASAT) is similar to ALT in that it is another enzyme associated with liver parenchymal cells.
11. Alkaline phosphatase (ALP) Alkaline phosphatase (ALP) is an enzyme in the cells lining the biliary ducts of the liver. ALP levels in plasma will rise with large bile duct obstruction, intrahepaticcholestasis or infiltrative diseases of the liver.
12. Bilirubin is a breakdown product of heme, a part of hemoglobin in red blood cells. The liver is responsible for clearing the blood of bilirubin.
Bilirubin is taken up into hepatocytes conjugated to make it water-soluble, and secreted into the bile, which is excreted into the intestine.
13. Coagulation test
The liver is responsible for the production of coagulation factors. The international normalized ratio (INR) measures the speed of a particular pathway of coagulation, comparing it to normal.
If the INR is increased, it means it is taking longer than usual for blood to clot. The INR will only be increased if the liver is so damaged that synthesis of vitamin K-dependent coagulation factors has been impaired: it is not a sensitive measure of liver function.
14. HEPATITIS
15. Hepatitis
inflammation of the liver characterized by the presence of inflammatory cells in the tissue of the organ
can be self-limiting, healing on its own, or can progress to scarring of the liver.
is is acute when it lasts less than six months and chronic when it persists longer.
16. 17. Causes of acute hepatitis
Viral hepatitis: Hepatitis A through E (more than 95% of viral cause), Herpes simplex, Cytomegalovirus, Epstein-Barr, yellow fever virusadenoviruses.
Non viral infection: toxoplasma, Leptospira, Q fever,rocky mountain spotted fever
Alcohol
Toxins: Amaniia toxin in mushrooms, carbon tetrachloride, asafetida
Drugs: Paracetamol, amoxycillin, antituberculosis medicines, minocycline and many others
Ischemic hepatitis (circulatory insufficiency)
Pregnancy
Auto immune conditions, e.g., Systemic Lupus Erythematosus (SLE)
Metabolic diseases, e.g., Wilson's disease
18. symptoms
flu-like symptoms, common to almost all acute viral infections and may include malaise, muscle and joint aches, fever, nausea or vomiting, diarrhea, and headache.
More specific symptoms, which can be present in acute hepatitis from any cause, are: profound loss of appetite, aversion to smoking among smokers, dark urine, yellowing of the eyes and skin and abdominal discomfort.
19. Jaundice can be a late feature and may indicate extensive damage. Other features include abdominal fullness from enlarged liver or spleen, low grade fever and fluid retention
Extensive damage and scarring of liverleads to weight loss, easy bruising and bleeding tendencies.
Acne, abnormal menstruation, lung scarring, inflammation of the thyroid gland and kidneys may be present in women with autoimmune hepatitis
20. Causes of chronic hepatitis
Viral hepatitis: Hepatitis B with or without hepatitis D, hepatitis C causes chronic hepatitis
Autoimmune: Autoimmune hepatitis
Alcohol
Drugs: methyldopa, nitrofurantoin, isoniazid, ketoconazole
Non-alcoholic steatohepatitis
Heredity: Wilson's disease, alpha 1-antitrypsin deficiency
Primary biliary cirrhosis and primary sclerosingcholangitis occasionally mimic chronic hepatitis[4]
21. Stages of Chronic hepatitis
Pre-icteric stage- with early symptoms that are non-specific, flu-like symptoms, that include malaise, fatigue, headache, myalgia, anorexia, nausea and vomiting and diarrhea
Icteric- occurs a few days to weeks after the icteric stage and include jaundice, dark colored urine, light colored stools and steatorrhea
Post-icteric stage- a convalescent stage lasting a few weeks jaundice resolves and appetite returns
22. Hepatitis A
Accounts for 20-25% of cases of clinical hepatitis in the world
Formerly called infectious hepatitis
Caused by an RNA virus
Mode of transmission: oral-fecal, sexually
Incubation period:15-50 days, average of 30 days
Confers immunity against itself
23. Symptoms
Asymptomatic, mostly
Flu-like upper respiratory symptom
Low grade fever
Anorexia, indigestion
Jaundice and dark urine
24. Diagnosis
Large liver and spleen
HAV antibodies in the serum
Hepatitis A antigen in the stool
25. Prevention
Proper hygiene
Vaccine (Havrix and Vagta)
Administration of globulin
26. Management
Bed rest
Small frequent feedings
27. Hepatitis B
Can be found in blood, saliva, semen and vaginal secretions
Can be transmitted by blood, through mucous membranes and breaks in the skin and the placenta
Develops into a more chronic type or within 6 months
28. Symptoms
Resembles hepatitis A but has a longer incubation period
Symptoms are insidious and variable
Loss of appetite, dyspepsia
Generalized aching, malaise, weakness
Enlarged liver and spleen
Jaundice
Diagnosis: prsence of HBsAg and antibodies
29. Treatment and Prevention
Interrupt chain of transmission
Active and passive immunization
Antiviral agents
Bed rest
Adequate nutrition
30. Hepatitis C
Formerly referred to as non-A, non-B hepatitis
Mode of transmission: blood and body fluids
Incubation period: 15-160 days
Symptoms appear milder than HBV
31. Hepatitis D
Occurs in some cases of hepatitis B because the virus requires the hepatitis B surface antigen for its replication
Mode of transmission: blood and body fluids
Symptoms and treatment are almost the same with hepatitis B