Toxic Princples Flashcards
Cyanogenic Glycosides
MOA:
Acute: inhibition of cytochrome oxidase and inhibtion of cellular respiration
Chronic: neuronal degeneration
CS:
Dyspnea, salivation, dilated pupils, ataxia, musc tremors, seizures, cardiac arrhythmias
Piperdine Alkaloids
MOA:
Nicotinic effects (ganglionic & NM stimulation followed by blockade)
CS:
Ataxia, incoordination, birth defects (skeletal malformation, cleft palate)
Nitropropanol Glycoside
MOA:
Inhibits enzymes of Krebs cycles & oxidative phosphorylation
CS:
Cattle & sheep: resp and neurologic (cracker heels/roaring)
Horses & rodents: neurologic
Pyrrolizidine Alkaloids
MOA:
Hepatotoxic
CS:
Liver damage; hepatic photosensitization
Lily
MOA:
Unknown toxin causing nephrotoxocity in cats; causes GI irritation in cats & dogs
CS:
Salivation, V, depression, anorexia, polyuria followed by anuria & death
*ARF in cats only*
Insoluble Calcium Oxalates
MOA:
Needle-shaped calcium oxalate crystals penetrate oral mucosa, tongue, and through causing
CS:
Irritation of lips, mouth, throat; Vomiting
**All parts of the plant is toxic; animal has to chew it**
Cycasin
MOA:
Glycoside: GI irritation, liver damage, teratogenic, mutagenic, carcinogenic
BMAA: neurotoxic amino acid
Unknown: cause axonal degeneration in CNS
CS:
Dogs: V (w/or w/out blood), anorexia, D+, depression, sometimes seizures
Sheep: GI and wt loss
Cattle: neuronal signs (ataxia, weakness, wt loss)
Lectins
(Phytotoxins, toxalbumins)
MOA:
Inhibit cellular protein synthesis causing cell death
CS:
Severe GI signs, bloody D+, cyanosis, convulsions, liver & kidney damage
Alsike Clover and Red Clover
MOA:
Hepatotoxicity & secondary photosensitization (horses), hepatic encephalopathy
CS:
Lacrimation, photophobia, erythema, pruritus, edema, necrosis, sloughing
Tannic Acid
MOA:
Tissue damage: GI and kidney
CS:
Cattle: constipation, brown urine, anorexia, depression, rumen atony (GI/kidney)
Monogastrics: colic, depression, constipation, hemorrhagic D+, hemoglobinuria, hematuria, icterus (GI)
Grapes and Raisins
MOA:
Unknown toxin causes acute renal failure in dogs
CS:
V, signs of acute renal failure
*Only dogs*
Selenium
Acute: GI irritation & resp signs
Chronic: hoof & hair abnormalities
Solanine and Solanidine Alkaloids
MOA:
GI, CNS, resp, cardiac
CS:
GI signs; similar signs to atropine (V, mydriasis, drowsiness)
Protoanemonin
MOA:
Volatile oil released by hydrolysis of glycoside
CS:
Severe irritation of GI muscoa and dermatitis
Copper
Liver damage, hemolysis, methemoglobinemia
Anthraquinones
MOA:
Purgative
CS:
Severe GI signs and D+
Grayanotoxins
MOA:
Bind to Na channels & depolarize excitabile cells, GI irritation
CS:
Hypersalivation, V/D, regurg, colic, depression, recumbency, tachycardia, tachypnea, seizures, fever
*death d/t aspiration pneumonia
Gossypol
MOA:
Cardiotoxic & secondary liver damage, detroys seminiferous tubules, binds to proteins, amino acids, & iron
CS:
Chronic; male infertility, cardiac toxicity
**Monogastric animals more sensitive**
Propyl disulfide
MOA:
Damage of RBC membranes & hemolysis, Heinz body formation
CS:
Anorexia, ataxia, tachycardia, dyspnea, icterus, anion odor, abortion
Coumarin Glycosides
MOA:
Form dicoumarol in spoiled plants; antagonize vit K by inhibiting vit K epoxide reductase (inhibits CF 2,7,9,10)
CS:
Hemorrhage
Tx: vit K1 or whole blood
Indolizidine Alkaloids (Swainsonine)
MOA:
Inhibit lysosomal enzymes essneital for formation of glycoproteins; alteration of cell function in brain & many organs
CS:
Neuronal signs (locoism), depression, incoordination, ataxia, circling, infertility, congenital defects, heart failure, wt loss, poor performance, decr immune fxn
Diterpene Esters
MOA:
Direct irritation of skin & mucous membranes, activate protein kinase C resulting in cell damage & enzyme dysfunction
CS:
Irritation & blistering of skin and GI Mucosa, salivation, V/D +/- blood
*More severe in large animals*
Cardiac Glycosides
MOA:
Inhibit Na/K ATPase; also cause GI irritation
CS:
Severe GI signs, dilated pupils, convulsions, resp signs, bradycardia, cardiac arrest
Ergot Alkaloids
MOA:
Vasoconstriction, gangrene, abortion
CS:
Chronic presentation
Macadamia Nuts
MOA:
Toxin and MOA are unknown
CS:
Weakness (esp in HLs), depression, ataxia, tremors, hyperthermia, lameness, recumbency, V/D, colic, pale mm
Xanthine Alkaloids
(Caffeine, Theophylline, Theobromine)
MOA:
Blocks adenosine receptors; inhibits phosphodiesterase
CS:
Salivation, V/D, colic, CNS stimulation/seizures, musc tremors, tachycardia, hypotension, urination
Triterpene Acids
MOA:
Liver damage & hepatic photosensitization
CS:
Depression, anorexia, constipation/D+, icterus, photophobia, erythema, swelling, necrosis, sloughing
**Horses are resistant**
Isocupressic Acid
MOA:
Vasoconstriction and decr uterine blood flow (release of fetal cortisol)
CS:
Abortion in cattle
Resins or Resinoids
MOA;
Irritation of nervous or musc tissue
Senna
MOA:
Unknown myotoxin causes skeletal musc myopathy & cardiomyopathy
CS:
D+, musc weakness, recumbency, good appetite, myoglobinuria, coffee colored urine, tachycardia, death
*Seeds are most toxic*
Glucosinolate
(Thiocyanate glycosides)
MOA:
Antithyroid
CS:
Signs of hypoT4
Colchicine
MOA:
Antimitotic (binds to tubulin and nihibits spindle formation during cell division)
CS:
All oragn system toxicity
*rapidly dividing cells are most sensitive*
Carboxyatractyloside
(Sulfated glycoside)
MOA:
Hepatotoxicity
CS:
Liver is main target; excessive salivation, renal damage, hypoglycemia
Black Walnut
MOA:
Ingestion of fresh shavings made from heartwood
CS:
Laminitis
Pigweed
MOA:
Nitrate: methemoglobinemia/abortion; soluble oxalates: hypocalcemia & kidney damage; unknonw: renal tubular nephrosis in ruminants, pigs, and horses
CS:
Hypocalcemia, depression, weakness, incoordination, signs of renal failure
Steroidal Saponins
MOA:
Hepatogenic photosensitivity, GI irritation
CS:
Photosensitization & liver damage; hypersalivation, V/D +/- blood, colic, nausea
Dogs and cats: depression
Cats: dilated pupils
Lycorine
MOA:
Emetic and pergative
CS:
Anorexia, salivation, V/D, hypotension
Lg amts: musc tremors & seizures
**bulb is the most toxic**
Thiaminase
MOA:
Destorys thiamine in diet and produced vit B1 deficiency
CS:
Neurotoxicity: wasting, incoordination, posterior paralysis, musc rigidity, convulsive seizures
Truterpenoid Saponins
MOA:
Direct irritation of GIT
CS:
Salivation, anorexia, V/D, colic, hypothermia
Meliatoxins
MOA:
Enterotoxic, Neurotoxic
CS:
GI signs +/- blood, CNS and peripheral signs (similar to nicotine), death from resp failure
Calcinogenic glycosides
(Vit D analogs)
MOA:
Hypercalcemia (inhibits renal excretion); calcification of elastic tissues (arteries, ligaments, tendons, etc.)
CS:
Slow onset of lameness (6m-1yr), incr bone density; calcinosis
Quinones
MOA:
Primary photosensitization (directly from the plant)
CS:
Erythema, pruritus, edema, necrosis of the skin, secondary bacterial infections
Yellow starthistle & Russian Knapweed
MOA:
Toxins interact w/dopamine transporter resulting in death of dopaminergic neurons esp substantia nigra & globus pallidus
CS:
Sudden onset, inability to eat or drink, drowsiness interrupted by excitation, head down, dehydration
*Equine Nigropallidal Encephalomalacia*
Chewing dz
Diterpene Alkaloids
MOA:
Competitive blockade of nicotinic receptors
CS:
Sudden death (cattle), musc weakness, stiffness, staggering, bloating, recumbency, collapse
Monkshood: cardiac arrythmias
Tx: Physostigmine and neostigmine
Molybdenum
MOA:
Causes copper deficiency
CS:
Watery, bubbly D+, wasting, anemia, depigementation, demyelination, osteoporosis
Tetradymol
MOA:
Hepatogenic photosensitization
CS:
Sudden onset of anorexia, depression, icoordination, dyspnea, icterus, head pressing, skin swelling erytehma, necrosis, sloughing
**Sheep are most susceptible**
Soluble oxalates
MOA:
Hypocalcemia and precipitation of insoluble calcium oxalates in soft tissues
Kidney damage
CS:
Hypocalcemia, tetany
Lg doses can cause renal failure
Avocado
Goats, horses, rabbits, caged birds: cardiotoxicity
Cattle, horses, goats, rabbits: non-infectious mastitis & agalactica
Red Maple
MOA:
Unknown toxin in dired leaves causes hemolytic anemia, hemoglobinemia & Heinz body anemia in horses
CS:
Anorexia, depression, anemia, icterus, brown discoloration of mm, hemoglobinuria, dyspnea, cyanosis, death
*Horses*
Nitrate
Acute: GI irritation, methemoglobinemia, resp insuffieicny, abortion
Chronic: decr progesterone during pregnancy & abortion
Tropane Alkaloids
(Atropine, hyoscine, hyoscyamine)
MOA:
Similar to atropine
All parts of the plant are toxic
CS:
Mydriasis, dry mouth, tachycardia, hypertension, urine retention, hallucination, seizures
Tx: physostigmine
Dimethyl Sulfide
MOA:
Oxidation of RBCs forming Heinz bodies
CS:
Depression, hemoglobinemia, hemoglobinuria, icterus, cyanosis
Phytoestrogens
MOA:
Bind to estogen receptors
CS:
Infertility in males/females; decr libido & feminization in males
Taxine Alkaloids
MOA:
Inhibits Na/K ATPase (Causes excess IC calcium)
CS:
Cardiotoxic and GI (similar to glycosides)
**CI to give K+**
Ptaquiloside
MOA:
Death of precurosr cells in BM; neoplasia in uinary tract; tumors in upper GIT; retinal damage
CS:
Aplastic anemia (acute hemorrhage & anorexia), enzootic bovine hematuria (blood in urine, anemia, tachycardia, death), bright blindness in sheed
Muscarine
MOA:
Stimulation of muscarinic cholinergic receptors
CS:
CNS stimulation
Pyridine Alkaloids
MOA:
Low doses: depolarization of nicotinic receptors at autonomic ganglia, NMJ, and CNS
High doses: causes blockade
CS:
Rapid onset; excitation, salivation, lacrimation, V/D, tachypnea, musc twitching/weakness, dyspnea
Death d/t resp failure
