The methanol poisoning by oral intake or skin contact occurs occasionally, which may have serious consequences including blindness and/or death. Methanol and its metabolites, formaldehyde and formic acid, are associated with metabolic acidosis, visual dysfunction and neurological symptoms. At present, the mechanism of methanol poisoning primarily focuses on the cell hypoxia, the alteration of structure and biological activity induced by free radical and lactic acid. Meanwhile, methanol poisoning causes changes in the balance between the production of free radicals and antioxidant capacity and in the proteases-protease inhibitors system, which lead to a series of disturbances.
Acidosis/chemically induced* ; Animals ; Formaldehyde/poisoning* ; Formates/poisoning* ; Free Radicals/metabolism* ; Humans ; Methanol/poisoning* ; Nervous System/pathology* ; Oxidoreductases Acting on CH-NH Group Donors/metabolism* ; Proteins/metabolism* ; Vision Disorders/pathology*

OBJECTIVE: To investigate concentration and distribution in blood and tissues of formic acid after methanol intoxication in rats. METHODS: The Sprague-Dawley rats were divided into groups for control group and 3-day and 7-day intoxication treatment groups. The experimental groups were administered methanol by gavage with the initial dose of 8 mL/kg and followed with 4 mL/kg supplemental dose 24 h later. After 3 days and 7 days later, rats were killed by decapitation. Then samples of cardiac blood, liver, kidney, brain, heart and stomach of each group were collected. Formic acid concentrations were detected by high performance liquid chromatography. RESULTS: Formic acid concentrations in tissues were higher than in blood. Compared with 3-day intoxication group, there was an increase formic acid of concentration in brain and stomach in 7-day intoxication group, while a decrease in liver and kidney (P < 0.05). CONCLUSION High performance liquid chromatography could be used to accurately detect formic acid. As the metabolite of methanol, formic acid accumulates in rat blood and tissues after intoxication and the concentrations in organs and tissues are obviously higher than in blood.
Animals ; Brain/metabolism* ; Chromatography, High Pressure Liquid ; Formates/blood* ; Kidney/metabolism* ; Liver/metabolism* ; Methanol/poisoning* ; Rats ; Rats, Sprague-Dawley ; Tissue Distribution