5. hormones Flashcards
which one is the active form and which one is the stored form?
insulin monomer and insulin hexamer
insulin monomer - biologically active
insulin hexamer - stored form
how many amino acids does the insulin A chain have?
21 amino acid residues
how many amino acids does the insulin B chain have?
30 amino acids
where does insulin lispro get it’s name
due to the amino acids PRO and LYS found in the B chain (reverse sequence is insulin lispro)
describe the effect of insulin on glucose uptake and metabolism
- insulin binds to the insulin receptor
- translocation of Glut-4 transporter to the plasma membranes
- influx of glucose
- glycogen synthesis
- glycolysis
- fatty acid synthesis
what tissues utilize glucose
- muscle
- adipose
- liver
what tissues stores fatty acids
- adispose
- liver
explain how glucose dependant insulin is released from beta cells
- glucose inserts the beta cells through GLUT2
- ATP is produced which closes the potassium channel causing depolarization
- Ca channels open which causes as influx of Ca
- IP3 and DG triggers additional release of Ca
- Ca activates insulin expression gene via CREB
- exocytosis of stored insulin is released
this is a metabolic disorder, specifically affecting carbohydrate metabolism. a common symptom of this disorder is excessive urine production.
diabetes mellitus (DM)
this type of diabetes is generally due to autoimmune destruction of the insulin-producing cells. formerly known as insulin-dependant diabetes, childhood diabetes or juvenile-onset diabetes. can only be treated only with insulin. treatment must be continued indefinitely at present. without insulin ketosis and diabetic ketoacidosis can develop which can lead to coma or death.
type I DM
involves isolating islets from a cadaveric donor pancreas using a mixture of enzymes called Liberase
Edmonton protocol
this type of diabetes is due to a combination of defective insulin secretion and defective responsiveness to insulin. previously known as adult onset diabetes, maturity onset diabetes or non-insulin dependant diabetes. it is first treated by changes in: physical activity, diet and weight. next it is treated with oral antidiabetic drugs and if these fail, insulin therapy is used
type 2 DM
this type of diabetes is a combination of inadequate insulin secretion and responsiveness, resembling type 2 diabetes. it develops during pregnancy and may improve or disappear after delievery
gestation DM/type 3 DM
in 1936, Hagedorn discovered that adding _______ to insulin prolongs the effect of insulin
protamine
what does NDH insulin stand for
Neutral Protamine Hagedorn
this type of insulin has an onset within 30 mins and lasts 6-8 hours. its max effect occurs at 1-3 hours and should be used 30-60 mins before a meal
regular (rapid onset, short acting)
this type of insulin has an onset within 2 hours and lasts 18-26 hours. its max effect occurs between 4-12 hours
NPH (slower onset, longer duration)
this type of insulin has an onset of 2-4 hours and lasts 18-26 hours. its max effect occurs between 6 and 12 hours.
Lente insulin (intermediate-acting)
this type of insulin is chemically modified and should be given within 15 minutes of a meal
ultarapid-acting insulin analog, insulin lispro injection [Humalog(r)]
in both of these types of insulin’s, the penultimate lysine and proline residues on the C-terminal end of the B-chain are reversed.
- do not alter receptor binding
- block the formation of insulin dimers and hexameters which gives maximum monomeric insulin to be available for postprandial (after meal) injections
- mixed solution and suspension
regular and ultra-rapid insulins
in this ultra rapid insulin, the lysine and proline residues on the C-terminal end of the B-chain are affected
insulin lispro (e.g. Humalog)
in this ultra rapid insulin, the aspartate residue on the C-terminal end of the B-chain is affected
insulin aspart (e.g. novo log)`
in this ultra rapid insulin, the glutamic acid residue on the C-terminal of the B-chain is affected
insulin glulisine (e.g. apidra)
this is a once-a-day product used for DM. its structural modifications include two arginine added to the C-terminus of the B-chain.
Lantus
this is a OD or BID s.c. insulin for type 1 DM or adult patients with type 2 DM who require a basal (long-acting) insulin for the control of hyperglycaemia. B29-lysine is conjugated with a myristic acid. this myristylated insulin has a high affinity for serum albumin therefore increasing its duration of action.
Levemir
this is a 37 amino acid hormone secreted by the beta cells of the pancreas in response to food intake.
amyline
how are amylin and insulin different
insulin regulates the glucose disappearance from the bloodstream whereas amylin regulates the glucose appearance in the bloodstream from the stomach and liver
this injection (pramlintide acetate) is a synthetic analog of human amylin. differs in amino acid sequence from human amylin (25 alanine, 28 serine and 29 serine replaced by proline)
SYMLIN
true/false: in conjunction with insulin, amylin is used for the treatment of type 1 and insulin-using type 2 diabetics
true
how does SYMLIN regulate glucose levels
- by decreasing gastric emptying
- surpasses postprandial (after meals) glucagon secretion leading to suppression of endogenous glucose output from the liver
- modulates appetite by enhancing satiety. this effect is independent of nausea and may lead to weight loss
this is a clear, isotonic, sterile solution for s.c. administration. vials contain 0.6mg/mL of pramlintide (as acetate), 2.25 mg.mL of metacresol as a preservative, D-mannitol as a tonicity modifier and acetic acid and sodium acetate as pH modifiers
SYMLIN
this is a 29 amino acid peptide. it is synthesized and secreted from alpha cells of the islets of Langerhans. GlucaGen is a brandname. is used for treatment of hypoglycemia
glucagon
how does glucagon main the level of glucose in the blood
it binds to glucagon receptor on hepatocytes
- causing the liver to release glucose from glycogen through hydrolysis (glycogenolysis)
- as glycogen becomes depleted, glucagon then encourages the liver to synthesize additional glucose by bluconeogenesis. this glucose is released into the bloodstream.
these two processes cause glucose release by the liver, therefore preventing the development of hypoglycaemia
glycogenolysis and gluconeogensis
this is a polypeptide hormone synthesized and secreted by the anterior pituitary gland. stimulates growth and cell reproduction in humans and other vertebrate animals.
growth hormone (or somatotropin)
what should be done in patients with a growth hormone excess (such as acromegaly and pituitary gigantism)
- surgery removal of GH-producing cells
- Somavert, hGH receptor antagonist
what should be done in patients with growth hormone deficiency (GHD)
- treated by replacing GH
this is a growth hormone product that is used for
- short stature in children due to growth hormone deficiency
- adult growth hormone deficiency
- growth failure due to Prader-Willi syndrome
- long term treatment of growth failure in children born small for gestational age
Genotropin
recognize these products that are products of _______________
- Humatrope (somatropin - rDNA origin for injection)
- Norditropin (somatropin - rDNA origin for injection)
- Protropin (somatrem for injection)
- Nutropin (somatropin - rDNA origin for injection)
- Saizen (somatropin - rDNA origin for injection)
- BioTropin (human growth hormone)
- Serostim (somatropin - rDNA origin for injection)
human growth hormone
this is produced primarily by the liver as an endocrine hormone (79 amino acids, structurally similar to insulin)
it is produced throughout life
- the highest rates occur during the pubertal growth spurt
- the lowest levels occur in infancy and old age
production can be ratarded by:
- under nutrition
- growth hormone insensitivity
- lack of growth hormone receptors
- failures of the downstream signalling pathway post GH receptor
insulin-like growth factor 1 (IGF-1)
what are the two receptors if IGF-1
- IGF-1 receptor (natural physiological)
- insu.in receptor: 1/10 of that of insulin
rare diseases can be characterized by inability to make ______ such as a distinctive type of growth failure termed Laron dwarfism which does not respond well to growth hormone treatment.
IGF-1
is medication is used for long-term treatment of growth failure in children with severe primary IGF-1 deficiency or with growth hormone gene deletion
Increlex
this can be described as having large extremities. symptoms include:
- soft tissue swelling of the hands and feet
- brow and lower jaw perfusion
- enlarging hands
- enlarging feet
acromegaly
> 90% of acromegaly patients have overproduction of GH which is caused by a benign tumour of the pituitary gland called an _______
adenoma
what happens in the body of acromegaly patients
- overproduction of GH
- when GH is produced into the bloodstream, there is then production of insulin-like growth factor (IGF-1)
- IGF-1 stimulates the growth of bones and other tissues
- abnormal growth of soft tissues and skeleton + signs and symptoms of acromegaly and gigantism
the effects of this include a decrease in IGF-1 production at the GH receptor level and decrease in IGF binding protein-3
growth hormone receptor antagonist
this medication is used for the treatment of acromegaly. it is structurally altered hGH therefore it acts as an antagonist of GHR. pegylation leads to a half life of 33 to 77 hours. it is supplied as a lyophilized powered. DO NOT SHAKE
Somavert
what inhibits GH secretion
- GH prodcution
- IGF-1
- Somatostatin
what promotes GH secretion
- growth hormone-releasing hormone (GRHR)
- stress, sleep, exercise
this is a hormone synthesized and secreted by gonadotropes in the anterior pituitary gland. in women, this hormone stimulates the growth of immature Graafian follicles to maturation in the ovary. in men, this hormones enhances the production of androgen-binding protein by the Sertoli cells of the testes and is essential for spermatogenesis.
Follicle stimulating hormone (FSH)
this medication is used for
- women undergoing assisted reproductive treatments such as INF and for the induction of ovalation to achieve pregnancy
- induction of spermatogenesis in mean with primary and secondary hypogonadotropic hypogonadism
Gonal-F, The Follistim AQ Cartridge for use with Follistim Pen or Follistim AQ vial
this is a type of growth factor that stimulates the activity of epithelial cells. management of oral mucositis (sore mouth and throat) due to chemo and radiation therapy
keratinocyte growth factor (KGF)
there are 5 phases to this process
phase 1: initiation with DNA initiation
phase 2: signalling with generation of messengers
phase 3: amplification with apoptosis tissues injury
phase 4: ulceration with pain
5. healing with tissue growth
oral mucositis
this medication is a human KGF produced by recombinant DNA technology in E.coli.
- differs from endogenous human KGF: the first 23 N-terminal amino acids have been deleted which increases protein stability
- it is used to treat severe oral mucositis in patients undergoing chemotherapy. needs to be refrigerated and protected from light
Kepivance (Palifermin)
this is a polypeptide that belongs to the transforming growth factor beta (TGF-beta) superfamily of cytokines. plays an important role in the development of bone and cartilage.
- InductOs is a medication based on this peptide.
Bone morphogenetic protein 2 (BMP-2)
this may be used for wound healing
- one of the cytokines that regulate cell growth, division and angiogenesis
platelet-derived growth factor (PDGF)
_______ is produced by recombinant DNA technology by insertion of the gene for the B chain of PDGF into the yeast, Saccharomyces cerevisiae. a homodimer composed of two identical B chains (PDGF-BB) that are bound together by disulphide bonds
- REGRANEX gel contains _________ (0.1%, rhPDGF-BB) for topical use for chronic diabetic ulcers
becaplermin
