Cardiac Toxins (Gossypol) Flashcards
Gossypol Mechanism of Action
Lipid soluble –> bile excretion into feces as gossypol-Fe complex
Ethylene Glycol: Mechanism of Action
- Metabolite (glycolic acid) –> CNS depression
- Metabolite (glycolic acid) –> severe metabolic acidosis, electrolyte abnormalities, and cytotoxicity
- Oxalate crystals –> mechanical obstruction and cytotoxicity
- Acute oxalate necrosis
Importsant to note that crystals in the urine indicates EXPOSURE, not that renal damage has occurred yet.
Gossypol Diagnosis Criteria
- Feeding/have access to: cottonseed
- Clinical signs –> combo of the three
- Analytical testing: -FREE GOSSYPOL IN DIET
Macadamia Nuts: General info
- Affects dogs only
- Cases occur more commonly where macadamia nuts are grown
- Can cause additionall issues (like all nuts): fat –> pancreatitis, poor digestion
Macadamia Nuts: Clinical Signs
- 3-6 hour: lethargy, vomitting, hyperthermia
- 6-12 hour: hindlimb (+/- forelimb) weakness, reluctance to move, ataxia, tremors,
Macadamia Nuts: Toxicity and Mechanims of Action & Treatment:
- Trigger dose = 1 nut/kg BW
- Mechanism of Action: idk
- Treatment: 1) Decontaminate (emesis, cathartic, AC). 2) Monitor Temperature and hydration 3) Methocarbamol for tremors if present
With regards to gossypol toxicity, what are the lesions like for this?
Gross –> - None
- signs of both sided heart failure
- Icterus
- anemia
- hemoglobinemia/hemglobinuria
Hiostological –> - cardiomyopathy
- centrilobular necrosis
- +/- abomastitis
- +/- tubular necrosis
Ethylene glycol: Clinical signs
- Clinical signs vary depending upon the dose, time, and stage in the cycle
- Stage one 1-3 but upt to 12 hours: CNS depression and PU/PD, vomitting, and death
- Stage 2: within 6-8 but up to 12 hours –> 1)metabolic acidosis 2) tachypnea, isosthenuria, and CNS depression
- ## stage 3: 6-12 up to 24 hours –> 1) oliguric/anuric renal disease –> failure 2) lethargy, vomitting, abdominal discomfort 3) seizures
Ethylene glycol: clinical pathology
- increased osmolality or increased anion gap
- **metabolic acidosis
- ionized or total hypocalcemia
- crystaluria: indicates exposure
- stage 3 azotemia
Ethylene glycol: general information
- antifreeze: contains > 95% ethylen glycol
- could also contain 1) propylene glycol 2) methanol 3) diethylene glycol
- Need to ask client for specific agent –> active ingredient
Ethylene glycol: lesion
- gross: nonspecific, common not to see anything
- Histological: proximal tubule degeneration/necrosis; birefringent calcium oxalate crystals
Ethylene glycol: Treatment
- Fluid therapy: dehydration, maintenace, promote renal excretion, support kidneys
- Monitor continuously: BW, Ca, ACid-base, urination
- Ethanol –> **dont use in stage 3; ethanol acts as a cmpetitive inhibitor for alcohol dehydrogenase
-Correct acidosis, Ca, get them to eat
What is the penumonic for Hypercalcemia and explain each letter
- Goshdarnit
- Granulomatous
- osteolytic process
- spurious
- humoral hypercalcemia of malignancy
- Hyperparathyroidism & hyperthyroidism
- Vitamin toxicity (vitamin D)
- Addisons disease
- Renal
- Neoplasia/nutritional
- Idiopathic/iatrogenic
- Tumor
Discuss mini topic of ice melts –> main problem it causes and treatment
- Causes oral/dermal irritation with additional GI signs
- electrolyte imbalance with large ingestions; specifically, it causes hyperkalemia, hypermagnesemia, and hypernatremia
Treatment
- Do NOT administer activated charcoal or induce emesis
- Treat sympotomatically with anti-emetics and GI protectants
Discuss gossypol toxicity and the general information about it
Toxicity:
- cardiac toxin (with some skeletal muscle effects)
- Two forms:
- 1) free = unprocessed sedd thats potentially toxic
- 2) Protein other bidning = processed and NOT toxic
ANimal effects: immature ruminants are more sensitive to the toxin than matute ruminants
