study d7

Question 1

insulin

how it works

Answer 1

Insulin (reduces blood glucose levels)
* stimulates transport of glucose from blood to insuline-sensitive tissues (muscle, adipose tissue)
* increases glycogen synthesis
* increases triglyceride synthesis
* increases protein synthesis (anabolic hormone)
* inhibits gluconeogenesis
* inhibits lipolysis

Regular insulin as produced by our pancreas
The pancreas is always releasing a little bit of insulin the background to affect lipolysis for eg.

Question 2

insulin

types, clinical use, adverse effects

Answer 2

• Intermediate and long duration forms have low solubility and gradually dissolve over longer periods of time (never injected i.v)
• short duration, fastest acting
• Short duration, slower acting,
• intermediate duration, slow acting
• Long duration, slowest acting

Clinical uses:
* treatment of type 1 and type 2 diabetes mellitus
* also used to treat hyperkalemia

Adverse effects:
* hypoglycemia
* tachycardia/palpitations, sweating and nervousness
* headache, confusion, drowsiness convulsions, coma
lipohypertrophy at injection site

Question 3

sulfonylureas, biguanides, glitazones

antuhyperglycemic diabetes drugs

Answer 3

Sulfonylureas
gliclazide (Diamicron) glyburide (Diabeta) (p.o.)
promote insulin secretion by the pancreas

Biguanides
metformin (Glucophage) (p.o)
decreased production of glucose (liver)
increased uptake of glucose (muscles, adipose)

Glitazones
rosiglitazone (Avandia) (p.o.)
decreased insulin resistance
adverse effects: retention of fluid / heart failure

Question 4

GLP1 agonist, DPP-4 inhibitors

Answer 4

Glucagon Like Peptide (GLP)-1 Receptor Agonists
* iraglutide (Victoza), semaglutide (s.c.)
* increase effect of endogenous incretin* (GLP-1),
* increases glucose-dependant release of insulin 


side effects:
decreased appetite; risk of thyroid cancer



Dipeptidyl peptidase-4 (DPP-4) Inhibitors
Sitagliptin (Januvia), saxagliptin, linagliptin (p.o.)
* increases incretin (GIP, GLP-1) levels by inhibiting DPP-4, 
an enzyme that normally inactivates the incretin hormones
* incretins then increase release of insulin

Question 5

plasma lipid levels

Answer 5

• Lipoproteins regulate the transport of cholesterol and triglycerides
• Low Density Lipoproteins (LDLs) initiate and fuel the development of atherosclerosis.
• HDLs may assist in reduce cholesterol levels in atherosclerotic plaques.

All drugs discussed in this section:

* reduce LDL levels
* reduce triglycerides* (except for bile acid binding resins)

Question 6

HMG-CoA reductase inhibitors + adverse effects

Answer 6

HMG-CoA reductase Inhibitors (statins)
atorvastatin, rosuvastatin and others

adverse effects:
gastro-intestinal disturbances
elevation of liver enzyme tests
can cause myopathies*
myalgia: muscle pain; 
normal creatine kinase (CK) plasma levels
myositis (muscle inflammation): muscle pain + elevated CK

rhabdomyolysis:
elevated myoglobin (blood, urine)

Question 7

cholesterol abrosption inhibitors and PCSK9 inhibitors

Answer 7

Cholesterol Absorption Inhibitor (ezetimibe)
* blocks absorption of cholesterol from intestine

PCSK9 Inhibitors (evolocumab, alirocumab)
* monoclonal antibodies that target PCSK9 (LDL receptor inactivators)
result = more LDL receptors = decreased circulating levels of LDL
adverse effects: injection site reactions, … 


Question 8

bile acid sequesterants

Answer 8

nonabsorbable resin that binds to bile acids (and other substances) in the GI tract and promote their excretion
body uses cholesterol to replace lost bile acids

adverse effects:
constipation (often administered with a laxative)

Question 9

thyroid horomones

principal actions

Answer 9

synthetic preparation of thyroxine (T4),
inactive precursor of the active form = triiodothyronine (T3)

thyroid hormones have three principal actions:
1. stimulation of energy use,
2. stimulation of the heart and
3. promotion of growth and development

Question 10

drugs for hyperthyroidism

Levothyroxine

Answer 10

used for the treatment of hypothyroidism
half-life = 7 days; 4-6 weeks before observing maximal effect
excessively high doses = symptoms of hyperthyroidism:
tachycardia, angina, tremor, nervousness, insomnia, hyperthermia, ↑ intestinal motility and sweating

Question 11

other drugs used to treat hyperthyroidism

Answer 11

methimazole, propylthiouracil*
Inhibit activation of T4 to T3

adverse effects: 
liver injury*, rash, arthralgia, hypothyroidism (at high doses), agranulocytosis (rare)