Alt and ast activity assay kits

To determine an appropriate dose of TAA and the exposure time, we
divided catheterized animals, 15 guinea pigs (6 weeks of age) and 15 rats (10
weeks of age), into five groups each (n = 3 per dose) and injected each group IP
with either vehicle (saline at 3 mL/kg) or TAA (25, 50, 100, or 200 mg/kg). We
selected IP route of injection to minimize the additional compounding factors of
toxicant bioabsoprtion and distribution when administered via an oral gavage. In
guinea pigs, vehicle or TAA was injected at 8 a.m., and samples of blood (200
μl/collection) were collected from the jugular vein just before treatment
(at 8 a.m.) and 3, 6, 9, 24, 27, 30, and 33 h after each treatment dose (Figure 1A). In rats, vehicle or TAA was
injected at 6 a.m., and blood samples (200 μl/collection) were collected
just before treatment (at 6 a.m.) and 3, 6, 9, 12, 24, 27, 30, 33, and 36 h
after each treatment dose (Figure 1C). In
both guinea pigs and rats, after the last blood collection, animals were
anesthetized by intravenous administration of sodium pentobarbital (50 mg/kg)
through the jugular vein, and the liver was harvested and fixed with a 10%
formaldehyde solution. Activities of plasma alanine aminotransferase (ALT) and
aspartate aminotransferase (AST) were measured using ALT and AST activity assay
kits (Sigma-Aldrich, St Louis, MO), respectively.