An intermediate syndrome after parathion poisoning

The organophosphate insecticides have become widely used in agriculture and in home gardening. There has been an increase in accidental and intentional poisoning. Almost all these compounds are potent cholinesterase inhibitors, and signs of poisoning are attributable to the accumulation of acetylcholine. The local absorption of these compounds from the conjunctiva, upper respiratory tract and skin following exposure to the aerosol or dust used in agricultural work, produces mild symptoms and is rarely of consequence except in accidents due to careless handling. The severe type of poisoning is caused usually by ingestion of the compound(s), and accumulation of large amounts of acetylcholine is fatal if not antagonized rapidly by atropine in large and continuous doses, together with respiratory support. Pyridine-2-Aldoxime Methiodide (P-2-AM) has been reported to be successful in treating Parathion poisoning. There is experimental evidence that it is not of similar value in some other organophosphorus insecticide poisoning.

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ACETYLCHOLINE IN PERIPLANETA AMERICANA L.: IV. THE SIGNIFICANCE OF ESTERASE INHIBITION IN INTOXICATION, ACETYLCHOLINE LEVELS, AND NERVOUS CONDUCTION

Canadian Journal of Biochemistry and Physiology ◽

10.1139/y60-165 ◽

1960 ◽

Vol 38 (1) ◽

pp. 1363-1376 ◽

Cited By ~ 1

Author(s):

E. H. Colhoun

Keyword(s):

Topical Application ◽

Periplaneta Americana ◽

Nervous Activity ◽

Esterase Inhibition ◽

Parathion Poisoning ◽

Nervous Transmission ◽

Nervous Conduction

Inhibition of ali-esterase (ALiE) of roaches by injections of tri-ortho-cresyl phosphate (TOCP) did not result in organophosphorus intoxication. Acetylcholinesterase (AChE) was not inhibited. Topical application of either tetraethylpyrophosphate (TEPP) or O,O-diethyl O-p-nitrophenyl phosphorothioate (parathion) to roaches treated with TOCP resulted in poisoning, inhibition of AChE, increases in the amount of acetylcholine (ACh), and disturbances in electrical nervous activity. Similar results were found for roaches treated only with either TEPP or parathion, but prostration was achieved more quickly in roaches first treated with TOCP, suggesting that TOCP treatment potentiated TEPP and parathion poisoning. Studies of electrical nervous activity in roaches showed that nervous conduction was not interfered with by ALiE inhibition. Synaptic nervous transmission was disrupted by inhibition of AChE with TEPP. Axonic nervous transmission was unimpaired although AChE was found to be inhibited.

Download Full-text

ACETYLCHOLINE IN PERIPLANETA AMERICANA L.: IV. THE SIGNIFICANCE OF ESTERASE INHIBITION IN INTOXICATION, ACETYLCHOLINE LEVELS, AND NERVOUS CONDUCTION

Canadian Journal of Biochemistry and Physiology ◽

10.1139/o60-165 ◽

1960 ◽

Vol 38 (11) ◽

pp. 1363-1376 ◽

Cited By ~ 17

Author(s):

E. H. Colhoun

Keyword(s):

Topical Application ◽

Periplaneta Americana ◽

Nervous Activity ◽

Esterase Inhibition ◽

Parathion Poisoning ◽

Nervous Transmission ◽

Nervous Conduction

Inhibition of ali-esterase (ALiE) of roaches by injections of tri-ortho-cresyl phosphate (TOCP) did not result in organophosphorus intoxication. Acetylcholinesterase (AChE) was not inhibited. Topical application of either tetraethylpyrophosphate (TEPP) or O,O-diethyl O-p-nitrophenyl phosphorothioate (parathion) to roaches treated with TOCP resulted in poisoning, inhibition of AChE, increases in the amount of acetylcholine (ACh), and disturbances in electrical nervous activity. Similar results were found for roaches treated only with either TEPP or parathion, but prostration was achieved more quickly in roaches first treated with TOCP, suggesting that TOCP treatment potentiated TEPP and parathion poisoning. Studies of electrical nervous activity in roaches showed that nervous conduction was not interfered with by ALiE inhibition. Synaptic nervous transmission was disrupted by inhibition of AChE with TEPP. Axonic nervous transmission was unimpaired although AChE was found to be inhibited.

Download Full-text