Page 269 - Veterinary Toxicology, Basic and Clinical Principles, 3rd Edition

236 SECTION | II Organ Toxicity

VetBooks.ir study, cardiac variables were normal on auscultation post- Akera, T., Ku, D.D., Frank, M., Brody, T.M., Iwasa, J., 1976. Effects of
1
1
grayanotoxin I on cardiac Na K -adenosine triphosphatase activ-
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ity, transmembrane potential and myocardial contractile force. J.
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sampled dogs (Segev et al., 2008; Lervik et al., 2010). The
Guide B-808, New Mexico State University, College of Agriculture
myocardial injury was verified by ECG performed posten-
and Home Economics, Las Cruces, NM.
venomation. Myocardial damage postenvenomation was
Aniszewski, T., 2007. Alkaloids - Secrets of Life. Elsevier, New York.
also shown by the increase of cardiac-specific troponin I.
Aslan, S., Erdem, A.F., Uzkeser, M., Cakir, Z., Cakir, M., Akoz, A.,
Polyvalent antivenoms are available for the treatment 2007. The Osborn wave in accidental hypothermia. J. Emerg. Med.
of most pit viper bites. Coral snake bites require neuro- 32, 271 273.
toxic antivenom. Aslani, M.R., Movassaghi, A.R., Mohri, M., Abbasian, A., Zarehpour,
M., 2004. Clinical and pathological aspects of experimental oleander
(Nerium oleander) toxicosis in sheep. Vet. Res. Commun. 28,
CANTHARIDIN 609 616.
Barbosa, R.R., Fontenele-Neto, J.D., Soto-Blanco, B., 2008. Toxicity in
Blister beetles prefer alfalfa fields where large swarms
goats caused by oleander (Nerium oleander). Res. Vet. Sci. 85,
tend to congregate. When these fields are harvested, the
279 281.
blister beetles are crushed and incorporated into the bales
Barceloux, D.G., 2008. Medical Toxicology of Natural Substances:
of hay. They contain a poisonous substance known as Food, Fungi, Medicinal Herbs, Plants and Venomous Animals.
cantharidin. It is an inhibitor of the serine threonine pro- Wiley, Hoboken, NJ.
tein phosphatase. Cantharidin blocks the adenosine A 1 Beasley, V., 1999. Other Plants that Affect the Heart. ,http://www.ivis.
receptors, regulates myocardial oxygen consumption, org/advances/Beasley/Cpt14e/chapter_frm.asp?LA51. (accessed
yielding antiadrenergic effects in ventricular cardiac myo- 26.01.11.).
cytes (Narayan et al., 2000). Cantharidin can exert a posi- Bentur, Y., Taitelman, U., Aloufy, A., 2003. Evaluation of scorpion
tive inotropic effect in cardiac muscle by increasing stings: the poison center perspective. Vet. Hum. Toxicol. 45,
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calcium influx (Neumann et al., 1995).
Berger, K., Guss, D., 2005. Mycotoxins revisited: part I. J. Emerg. Med.
In equids, the LD 50 of cantharidin is reported to be
28, 53 62.
1 mg/kg b.w. (Guglick et al., 1996). A dose of 4 g of
Boelsterli, U.A., 2007. Mechanistic Toxicology: The Molecular Basis of
dried beetles is lethal to a horse and 1 1.5 mg/kg b.w.
How Chemicals Disrupt Biological Targets. CRC Press, Boca Raton,
for cats and dogs. The cardiac symptoms of cantharidin FL.
poisoning include increased heart rate and myocardial Botha, C., 2013. Cardiac glycoside intoxication. ,http://www.afrivip.org/
dysfunction. There is no antidote for cantharidin, but sites/default/files/cardiac_glycoside_intoxication_complete_2.pdf..
symptomatic treatment is recommended with administra- Brack, M., Rothe, H., 1982. Organophosphate poisoning in marmosets.
tion of fluids and maintenance of serum electrolytes. Lab Anim. 16, 186 188.
Burrows, G.E., Tyrl, R.J., 2006. Handbook of Toxic Plants of North
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CONCLUDING REMARKS AND FUTURE Chan, T., 2009. Aconite poisoning. Clin. Toxicol. (Phila). 47, 279 285.
DIRECTIONS Chang, C., 2009. Amatoxin Toxicity in Emergency Medicine. ,http://
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Cardiac problems in domestic animals are primarily due 25.02.11.).
to toxic plants, chemicals, and envenomation, most of Cheeke, P.R., 1989. Toxicants of Plant Origin. CRC Press, Boca Raton,
which can be avoided. Genetics plays a secondary role to FL.
environmental factors (Detweiler, 1964). There is only a Cheeke, P.R., 1995. Endogenous toxins and mycotoxins in forage grasses
limited amount of published research on cases involving and their effect on livestock. J. Anim. Sci. 73, 909 918.
inadvertently affected animals. Animal cardiac responses Clark, J.G., 1979. Whorled milkweed poisoning. Vet. Hum. Toxicol. 21,
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have been extensively studied in the development of
Coltart, D.J., Hudson, R.E.B., 1971. Primary oxalosis of the heart: a
drugs. A considerable amount of work still needs to be
cause of heart block. Br. Heart J. 33, 315 319.
done on cardiotoxicity in animals caused by plants, che-
Detweiler, D.K., 1964. Genetic aspects of cardiovascular diseases in ani-
micals, and envenomation. mals. Circulation. 30, 114 127.
Doonan, G.R., Brown, C.M., Mullaney, T.P., Brooks, D.B., Ulmanis, E.
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