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Biomedical subjects

R Heywood

Publications and source records attributed to R Heywood.

At least 73 records · Page 4Linked to original sources

The toxicity of 1-amino-3-chloro-2-propanol hydrochloride (CL88,236) in the rhesus monkey.

The toxicity of 1-amino-3-chloro-2-propanol is associated with acute histopathological change in the medulla oblongata, characterised lesions of focal oedema. Continued administration results in neurological scars. Lesions can be induced at dose levels of 50 mg . kg-1 day-1. Clinical manifestations of neurological involvement are periods of slight incoordination and loss of balance in a few animals only.

Animals↗

Clioquinol toxicity in the dog.

A number of instances have been reported in the scientific literature in which acute intoxication with halogenated oxyquinolines has led in some species to convlusions, often followed by death. The toxicity of repeated doses of clioquinol has been investigated extensively in the dog. The clinical syndrome induced in this species is characterized by anorexia, weight loss, extremem muscle weakness and emaciation. In some animals surviving this impairment of condition for several weeks, neuropathy of the central nervous system, but not of the peripheral nerves ensued. It is suggested that these toxicological manifestations are less dependent on the dose-level than on the degree of absorption. Some suggestions regarding the aetiology of the lesions are made.

Animals↗

The oral toxicity of 1-amino-3-chloro-propanol hydrochloride (CL 88236) in rats.

1-amino-3-chloro-2-propanol (CL 88236) was administered by oral gavage for 12 consecutive weeks to rats at dose levels of 50, 250 and 500 mg/kg/day. All levels gave rise to toxicological effects. Epididymal necrosis and/or atrophy of the seminiferous epithelium was found for some males with each dose of CL 88236. The kidney and liver weights of male and female rats given CL 88236 were higher than control values but no histological changes were found in these organs.

Animals↗

Toxicology studies of linear alkylbenzene sulphonate (LAS) in rhesus monkeys. I. Simultaneous oral and subcutaneous administration for 28 days.

A toxicological investigation was performed with the linear alkylbenzene sulphonate (LAS) using 4 groups of 3 male and 3 female monkeys. Dosages were 0, 30, 150, 300 and 0, 0.1, 0.5, 1.0 mg/kg/day by simultaneous oral (p.o.) and subcutaneous (s.c.) administration respectively, for 28 days. At 300 p.o. and 1.0 s.c. mg/kg/day, the monkeys vomited frequently and usually within 3 hours of administration. An increased frequency of loose or liquid faeces was recorded for animals receiving 150 p.o. and 0.5 s.c. and 300 p.o. and 1.0 s.c. mg/kg/day. Fibrosis of the injection sites was found among all the test groups, the incidence and severity being dose related. Ophthalmoscopy, laboratory examination of blood and urine, organ-weight analysis and histopathological investigation did not detect any further treatment related responses. Previous reports concerning oral administration of tetrapropylene benzene sulphonates (ABS) to dogs record prompt emesis ascribed to local gastro-intestinal effects. Vomiting observed during this investigation was considered to be of possible central origin.

Administration, Oral↗

Toxicity of methyl testosterone in the beagle dog.

When methyl testosterone was administered orally to beagle dogs at dosage levels of 2, 4 and 6 mg/kg per day for 27 weeks, hepatotoxicity was induced. The change induced was characterized by enlargement of periportal hepatocytes and the presence of haemosiderin within macrophages. There was some evidence of recovery over a 13-week period.

Animals↗

The oral toxicity of clioquinol (5-chloro-7-iodo-8-hydroxyquinoline) in beagle dogs.

When clioquinol was administered to Beagle dogs, disturbances in gait which were associated with abnormal reflexes and reactions, were seen in animals receiving 250 and 400 mg/kg body weight per day. Histopathological examination of the central nervous system (CNS) showed pathological change in the posterior columns of the spinal cord.

Animals↗

Retinal detachment in the rat.

Retinal detachment is uncommon in the rat. Retinal atrophy, rosette formation and folding of the retina are some of the sequelae following reattachment.

Animals↗