33 terms

glucose metabolism

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drugs affecting glucose metabolism
Insulin
Glucagon
Oral hypoglycemics
Acarbose
Somatostatin
Diazoxide
IDDM
lack of insulin due to destruction of beta cells
dogs & cats
NIDDM
insulin may be lower or higher than normal but their is hyperglycemia
assoc w/ obesity
cats
stimulation of insulin secretion
glucose, aa, FAs, ketone bodies
GI hormones
stim of B2 adrenergic rec
vagal stim (M3 rec)
inhibition of insulin secretion
stim of a2 adrenergic rec
somatostatin
MOA of insulin
binds to insulin rec activating tyrosine kinase->phosphorylation of rec & proteins
effects of insulin
anabolic: inc glycogenesis, lipogenesis, protein syn, uptake of K into cells
dec glycogenolysis, lipolysis
*rapid/short acting insulin preps*
Regular (crystalline)
Semilente
(onset <1hr, DOA 5-16hr)
*Intermediate insulin preps*
NPH (isophane)
Lente
(onset 1-2 hr, DOA 18-24hr)
*slow/long acting insulin preps*
Ultralente
Protamine zinc (PZI)
(onset 4-6, DOA 24-36)
Only insulin prep given IV in emergency
*Regular (crystalline) *
Tx IDDM: Diabetic ketoacidosis
Emergency-inappetence & vomiting
-Regular insulin IV infusion or svl IM inj
-fluid therapy-correct acidosis
-high fiber diet (1/2 caloric needs)
Tx IDDM: uncomplicated
intermediate or long-acting insulin
high fiber diet
Tx NIDDM
dietary management (high fiber diet)
Oral hypoglycemics
Insulin
Acarbose (adjunctive therapy)
Adverse effects of insulin
hypoglycemia & insulin shock
hypoK
IR
HS rxns
rebound hyperglycemia
tx of hypoglycemia & insulin shock
dextrose-orally(best)/IV(unconscious)
glucagon-IM(slow effect)
drug interactions that dec hypoglycemic effect of insulin (may need to inc dose)
Sympathomimetics
a2 agonists
Diuretics (CAI, loop, thiazide)
Hormones (corticosteroids, GH, progestins, estrogens, glucagon, thyroid agents)
Phenytoin (anticonvulsant)
Phenothiazines
drug interactions that inc hypoglycemic effect of insulin
B-blockers
Oral hypoglycemics
Androgens
Anabolic steroids
ACE inhibitor
Alcohol
MAOI
Aspirin & phenylbutazone
Sulfonamides
Tetracyclines
ORAL hypoglycemics (sulfonylureas)
Glipizide
Glyburide
Glimepiride
MOA of oral hypoglycemics
inc basal insulin secretion (close K channels-depolarize cell)
inc glucose mediated insulin secretion
inc insulin binding
dec glucagon
use of oral hypoglycemics
Tx NIDDM in cats
**may exhaust beta cells->IDDM*
contraindications for oral hypoglycemic use
renal/hepatic insuf
pregnancy
antihyperglycemic used in diabetic dogs/cats with mild hyperglycemia
Acarbose
MOA of Acrabose
*slow elevation of blood glucose levels*
-competitively inhibit pancreatic alpha-amylase/glucosidases
-delay CHO digestion
-dec GI glucose absorption
stimulation of glucagon secretion
low glucose & FAs
protein intake
GI hormones & NTs
MOA of glucagon
G protein coupled rec->activate adenylyl cyclase->inc CAMP->protein kinase->substrate phos
glucagon effects
-inc hepatic glycogenolysis, gluconeo & lipolyis
-stim heart
-relax smooth mm in gut
therapeutic uses of glucagon
insulin induced hypoglycemia (dextrose not available)
cardiac stimulant (B-blocker OD)
Tx peri-parturient bovine ketosis
release of somatostatin
hypothalamus
D cells of islets of Langerhans
effects of somatostatin
inhibit release of insulin, glucagon, GH, GI hormones
management in dogs of:
insulinoma
glucagonoma
acromegaly
gastrinoma
Octreotide acetate (syn analog of somatostatin)
nondiuretic thiazide used in oral tx of insulinomas
Diazoxide
MOA of Diazoxide
inhibit insulin release from beta cells
stim catecholamine release