Physiological Effects of Parathion on the Cockroach Gut in Vivo and Correlation with External Symptoms of Poisoning12

Hopkins, Theodore L.; Rao, N. R.; Ameel, J. J.

doi:10.1093/jee/63.4.1086

Cited by 3 publications

(2 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…As to the site of loss, depletion of body fluids is usually attributed to increased regurgitation and excretion (Mobius & Wedekind, 1934; Klinger, 1936;Ludwig, 1946;Jochem, 1953Jochem, , 1956 Roan & Hopkins, 1961;Roberts et al, 1969), possibly after redistribution of the available water from the blood to the gut (Jochem, 1956;Hopkins, Rao & Ameel, 1970). Losses may also occur by increased transpiration through the spiracles (Ingram, 1955), through the integumental membranes of the body wall (Ludwig, 1946), and through the general integument (Buck & Keister, 1949;Chadbourne & Rainwater, 1953;Ingram, 1955).…”

Section: (3) Insecticide-induced Water Lossmentioning

confidence: 99%

“…T h e insect's body is often found swollen and distended upon treatment with insecticides, a condition that has been ascribed to 'swallowing of air' because of "constant movement of the mouth parts" (O'Kane et al, 1933;Coon, 1944;Wiesman & Kocher, 1951;Mansingh, 1965). However, Hopkins, Rao & Ameel (1970), who relieved the crop of parathion-poisoned locust (Leucophaea maderae F.) from accumulating gas, found it to refill with gas when the insects were completely paralysed and when no movements of the mouth parts were evident. Analysis of the gas content of the foregut revealed the accumulation of carbon dioxide, and a decreased oxygen concentration.…”

Section: (5) a New Conceptmentioning

confidence: 99%

See 1 more Smart Citation

Insecticides: Their Route of Entry, Mechanism of Transport and Mode of Action

Gerolt

1983

Biological Reviews

View full text Add to dashboard Cite

Summary (1) The assumption that the circulatory system of the insect is instrumental in transporting insecticides to their site of action appeared not to be based on good evidence. On the contrary, experiments specifically designed to test the hypothesis provided ample evidence to refute the idea. Salient points to disprove the haemolymph route of entry can be summed up as follows: (a) A topically applied dose of insecticide does not readily penetrate the insect and the minor fraction that does so is largely retained in the body wall. The small amount that actually passes into the blood is too small to cause symptoms of toxicity if injected into the haemocoel. (b) The amount of insecticide present in the haemolymph (and CNS) does not appear to have any bearing on toxicity ‐ internally introduced insecticides are, in fact, basically very much less toxic than those externally applied. Where injected doses appear to be more toxic than equal amounts topically applied, this is due to the boosting effect of organic solvent carriers. Tests with parabiotically joined insects provide support for the view that haemolymph‐borne insecticide is of no consequence. (c) The topographical proximity of the locus of external application with the site of action (the thoracic ganglia) seems to be important irrespective of the general direction of the blood flow, and this should not be so if the circulatory system was instrumental in the transport of insecticide. (d) The introduction into the haemocoel of material such as olive oil, which is an excellent absorbent for insecticides, does not affect the toxicity (speed of action) of externally applied compounds to a significant extent. It should have a pronounced effect if haemolymph‐borne insecticide were an essential element in the process of poisoning. (e) As judged by speed of action, blocking of the blood circulation does not hamper the insecticide's movement to the site of action. (2) Only two other feasible routes remain. (a) The insecticide might reach the CNS via peripheral nerves and nerve cord, but the results of histochemical assays of cholinesterase inhibition in the insect's CNS make the idea improbable for organo‐phosphates. The nerve route is also incompatible with the observation that a wax barrier blocked the movement in and over the body wall so as to delay the onset of symptoms of toxicity, as such a barrier would not hinder movement into lateral nerves near the locus of application. (6) The only other feasible alternative, i.e. entry by means of lateral transport via the integument of the body wall and tracheae, is supported by autoradiographic and other evidence which showed the insecticide to accumulate in the tracheal system. It is further supported by the fact that inter‐tracheal introduction is faster acting than topical treatment, indicating that the tracheal system offers a very effective pathway to the internal organs. (3) Regarding the mechanism of entry, earlier reviews and text books maintain this to be associated exclusively with penetration into and thr...

show abstract

Section: (3) Insecticide-induced Water Lossmentioning

confidence: 99%

Section: (5) a New Conceptmentioning

confidence: 99%

Insecticides: Their Route of Entry, Mechanism of Transport and Mode of Action

Gerolt

1983

Biological Reviews

View full text Add to dashboard Cite

show abstract

The mode of action of insecticides: Accelerated water loss and reduced respiration in insecticide‐treated Musca domestica L.

Gerolt

1976

Pestic. Sci.

View full text Add to dashboard Cite

Contact with organophosphorus, carbamate, organochlorine and pyrethroid insecticides caused accelerated water loss from all major parts of the integument of the housefly. The response appeared to be specific in that only insecticides, and not their truly non-toxic analogues, had this effect, specificity being also reflected in resistance and in synergistic and antagonistic responses. As an insecticide dispersed laterally in the integument the effect spread to more distant parts, including the intestinal and tracheal systems, its arrival in the tracheal system coinciding with a reduction in the rate of respiration. It is suggested that this reaction of the integument to contact with insecticides is the primary cause of eventual death. Interference with the water balance in the tracheal system affects the normal exchange of the respiratory gases and thus proper respiratory control, to which the insect reacts with symptoms of excitation and paralyses. Degeneration of vital tissues following the loss of water is probably ultimately responsible for the death of the insect.

show abstract