RAT-LIVER FORMAMIDASE (ARYL FORMYLAMINE AMIDOHYDROLASE), NATURAL SUBSTRATE OF WHICH IS N-FORMYLKYNURENINE, IS ACTIVE IN HYDROLYSIS OF METABOLIC INTERMEDIATES OF.../ACARICIDE/...FORMETANATE. /FORMETANATE/
IN RATS TREATED WITH FORMETANATE...60-80% OF URINARY EXCRETORY PRODUCTS WERE WATER-SOL CONJUGATES. MAJOR AGLYCONE WAS 3-HYDROXYACETANILIDE...& OTHER AGLYCONES INCLUDED 3-HYDROXYFORMANILIDE, 3-FORMAMIDOPHENYL-N-METHYLCARBAMATE & M-[[(METHYLAMINO)METHYLENE]AMINO]PHENYL-N-METHYLCARBAMATE. /FORMETANATE/
About 84% of formetanate injected into houseflies was metabolized in 4 hours. The major metabolite was 3'-hydroxyformanilide. Microsomes from housefly abdomen plus NADH resulted in only 10% metabolism of formetanate. /Formetanate/
Formetanate hydrochloride is a cholinesterase or acetylcholinesterase (AChE) inhibitor. Carbamates form unstable complexes with chlolinesterases by carbamoylation of the active sites of the enzymes. This inhibition is reversible. A cholinesterase inhibitor suppresses the action of acetylcholine esterase. Because of its essential function, chemicals that interfere with the action of acetylcholine esterase are potent neurotoxins, causing excessive salivation and eye-watering in low doses. Headache, salivation, nausea, vomiting, abdominal pain and diarrhea are often prominent at higher levels of exposure. Acetylcholine esterase breaks down the neurotransmitter acetylcholine, which is released at nerve and muscle junctions, in order to allow the muscle or organ to relax. The result of acetylcholine esterase inhibition is that acetylcholine builds up and continues to act so that any nerve impulses are continually transmitted and muscle contractions do not stop.
来源:Toxin and Toxin Target Database (T3DB)
毒理性
致癌性证据
癌症分类：人类非致癌性证据E组
Cancer Classification: Group E Evidence of Non-carcinogenicity for Humans
来源:Hazardous Substances Data Bank (HSDB)
毒理性
致癌物分类
对人类不具有致癌性（未被国际癌症研究机构IARC列名）。
No indication of carcinogenicity to humans (not listed by IARC).
Acute exposure to cholinesterase inhibitors can cause a cholinergic crisis characterized by severe nausea/vomiting, salivation, sweating, bradycardia, hypotension, collapse, and convulsions. Increasing muscle weakness is a possibility and may result in death if respiratory muscles are involved. Accumulation of ACh at motor nerves causes overstimulation of nicotinic expression at the neuromuscular junction. When this occurs symptoms such as muscle weakness, fatigue, muscle cramps, fasciculation, and paralysis can be seen. When there is an accumulation of ACh at autonomic ganglia this causes overstimulation of nicotinic expression in the sympathetic system. Symptoms associated with this are hypertension, and hypoglycemia. Overstimulation of nicotinic acetylcholine receptors in the central nervous system, due to accumulation of ACh, results in anxiety, headache, convulsions, ataxia, depression of respiration and circulation, tremor, general weakness, and potentially coma. When there is expression of muscarinic overstimulation due to excess acetylcholine at muscarinic acetylcholine receptors symptoms of visual disturbances, tightness in chest, wheezing due to bronchoconstriction, increased bronchial secretions, increased salivation, lacrimation, sweating, peristalsis, and urination can occur. Chronically high (>10 years) exposure leads to neuropsychological consequences including disturbances in perception and visuo-motor processing (A15321).
ORAL DOSE OF (14)C-FORMETANATE...WAS RAPIDLY ABSORBED & EXCRETED BY RAT; 85% IN URINE & 8% IN FECES. AFTER 72 HR, 2% OF THE (14)C WAS STILL RETAINED. /FORMETANATE/
Of a single dose of formetanate HCL to rats, 75% was excreted in the urine during the first 12 hr with peak concentrations observed at 6 hr. Within 24 hr after administration, 80% of the dose was eliminated in the urine and 6% in the feces ... . When 14-C-labeled formetanate HCL was orally administered to lactating goats at 1.4 mg/kg/day for 10 days, 80-90% of the dose was excreted in the urine within 24 hr of the last administration, and fecal excretion ranged from 1.3 to 6.6%. Two days after exposure began, radiolabel in the milk (as formetanate HCL) plateaued at 0.46 ppm. ...
