title: Assessment of acute oral and dermal toxicity of 2 ethyl-carbamates with activity against Rhipicephalus microplus in rats.
abstract: The acute oral and dermal toxicity of two new ethyl-carbamates (ethyl-4-bromophenyl-carbamate and ethyl-4-chlorophenyl-carbamate) with ixodicide activity was determined in rats. The oral LD50 of each carbamate was 300 to 2000 mg/kg, and the dermal LD50 of each carbamate was >5000 mg/kg. Clinically, the surviving rats that had received oral doses of each carbamate showed decreased weight gain (P < 0.05) and had slight nervous system manifestations. These clinical signs were evident from the 300 mg/kg dose and were reversible, whereas the 2000 mg/kg dose caused severe damage and either caused their death or was motive for euthanasia. At necropsy, these rats had dilated stomachs and cecums with diffuse congestion, as well as moderate congestion of the liver. Histologically, the liver showed slight degenerative lesions, binucleated hepatocytes, focal coagulative necrosis, and congestion areas; the severity of the lesions increased with dosage. Furthermore, an slight increase in gamma-glutamyltransferase, lactate dehydrogenase, and creatinine was observed in the plasma. The dermal application of the maximum dose (5000 mg/kg) of each carbamate did not cause clinical manifestations or liver and skin alterations. This finding demonstrates that the carbamates under study have a low oral hazard and low acute dermal toxicity.
authors.affiliation: Programa de Maestría y Doctorado en Ciencias de la Producción y de la Salud Animal, Universidad Nacional Autónoma de México, 04510 Ciudad Universitaria, DF, Mexico.
authors.forename: María Guadalupe
authors.initials: MG
authors.lastname: Prado-Ochoa
authors.affiliation: Programa de Maestría y Doctorado en Ciencias de la Producción y de la Salud Animal, Universidad Nacional Autónoma de México, 04510 Ciudad Universitaria, DF, Mexico.
authors.forename: Ricardo Alfonso
authors.initials: RA
authors.lastname: Gutiérrez-Amezquita
authors.affiliation: Laboratorio de Química Medicinal, Departamento de Ciencias Químicas, Facultad de Estudios Superiores Cuautitlán, Universidad Nacional Autónoma de México, 54714 Cuautitlán Izcalli, MEX, Mexico.
authors.forename: Víctor Hugo
authors.initials: VH
authors.lastname: Abrego-Reyes
authors.affiliation: Laboratorio de Química Medicinal, Departamento de Ciencias Químicas, Facultad de Estudios Superiores Cuautitlán, Universidad Nacional Autónoma de México, 54714 Cuautitlán Izcalli, MEX, Mexico.
authors.forename: Ana María
authors.initials: AM
authors.lastname: Velázquez-Sánchez
authors.affiliation: Departamento de Ciencias Biológicas, Facultad de Estudios Superiores Cuautitlán, Universidad Nacional Autónoma de México, 54714 Cuautitlán Izcalli, MEX, Mexico.
authors.forename: Marco Antonio
authors.initials: MA
authors.lastname: Muñoz-Guzmán
authors.affiliation: Departamento de Ciencias Biológicas, Facultad de Estudios Superiores Cuautitlán, Universidad Nacional Autónoma de México, 54714 Cuautitlán Izcalli, MEX, Mexico.
authors.forename: Patricia
authors.initials: P
authors.lastname: Ramírez-Noguera
authors.affiliation: Laboratorio de Química Medicinal, Departamento de Ciencias Químicas, Facultad de Estudios Superiores Cuautitlán, Universidad Nacional Autónoma de México, 54714 Cuautitlán Izcalli, MEX, Mexico.
authors.forename: Enrique
authors.initials: E
authors.lastname: Angeles
authors.affiliation: Departamento de Ciencias Biológicas, Facultad de Estudios Superiores Cuautitlán, Universidad Nacional Autónoma de México, 54714 Cuautitlán Izcalli, MEX, Mexico.
authors.forename: Fernando
authors.initials: F
authors.lastname: Alba-Hurtado
mesh_terms: D000284:Administration, Oral; D000818:Animals; D003404:Creatinine / Q000097:blood; D008099:Liver / Q000187:drug effects; D008297:Male; D051381:Rats; D048494:Rhipicephalus / Q000187:drug effects*; D012867:Skin / Q000187:drug effects*; D014520:Urethane / Q000031:analogs & derivatives / Q000494:pharmacology* / Q000633:toxicity
chemical_list: D014520:Urethane; D003404:Creatinine