Insecticide mode of action. Effect of dieldrin on ion movement in the nervous system of Periplaneta americana and Blattella germanica corckroaches

1967 ◽  
Vol 15 (4) ◽  
pp. 622-627 ◽  
Author(s):  
Mamoru. Hayashi ◽  
Fumio. Matsumura
1962 ◽  
Vol 39 (3) ◽  
pp. 319-324
Author(s):  
K. G. DAVEY

1. Addition of a homogenate of corpora cardiaca to the fluid bathing an isolated hind gut of Periplaneta produces an increase in tonus, amplitude, frequency and co-ordination of contractions. 2. The corpus cardiacum acts by stimulating cells in the upper colon to release an indolalkylamine. 3. This amine acts on the mucles through a peripheral nervous system which can function in isolation from the central nervous system.


1963 ◽  
Vol 40 (4) ◽  
pp. 763-773
Author(s):  
K. G. DAVEY ◽  
J. E. TREHERNE

1. The structure and mode of action of the proventriculus are described. 2. X-ray photographs have shown that as the crop empties the decrease in volume of the fluid is partially compensated for by the swallowing of air. 3. The effects of various factors upon the rate of crop-emptying have been studied using solutions of different osmotic pressures. Changes in viscosity, effected by the addition of methyl cellulose, produce only a minor reduction in crop-emptying. The frequency of opening of the proventricular valve is not proportional to the rate of crop-emptying over the whole range of concentrations used, and it is assumed that changes in other parameters must affect the process.


1961 ◽  
Vol 38 (2) ◽  
pp. 315-322
Author(s):  
J. E. TREHERNE

1. The influx of sodium and potassium ions into the central nervous system of Periplaneta americana has been studied by measuring the increase in radioactivity within the abdominal nerve cord following the injection of 24NA and 42K. into the haemolymph. 2. The calculated influx of sodium ions was approximately 320 mM./l. of nerve cord water/hr. and of potassium ions was 312 mM./l. of nerve cord water/hr. These values are very approximately equivalent to an influx per unit area of nerve cord surface of 13.9 x 10-2 M cm. -2 sec.-1 for sodium and 13.5 x 10-12 M cm. -2 sec.-1 for potassium ions. 3. The relatively rapid influxes of these ions are discussed in relation to the postulated function of the nerve sheath as a diffusion barrier. It is suggested that a dynamic steady state rather than a static impermeability must exist across the sheath surrounding the central nervous system in this insect.


2009 ◽  
Vol 201 (S602) ◽  
pp. 106-109
Author(s):  
Ilari Paakkari ◽  
Heikki Karppanen ◽  
Pirkko Paakkari

1959 ◽  
Vol 37 (1) ◽  
pp. 259-272 ◽  
Author(s):  
E. H. Colhoun

The levels of acetylcholine (ACh) in the thoracic nerve cords of cockroaches were increased by the topical application of 2,2-bis(p-chlorophenyl)-1,1,1-trichloroethane (DDT) and of tetraethyl pyrophosphate (TEPP), but only TEPP inhibited cholinesterase (ChE). Improvements in the correlation of symptoms, nervous activity, and ACh levels with ChE were obtained when nerve cords were homogenized in saline containing ACh, which prevented further inhibition of ChE by TEPP found to be present in blood and nervous tissue. There was a similarity in the distribution of ACh in thoracic nerve cords of roaches after topical treatment with TEPP and DDT but the physiological properties of the blood revealed differences in the mode of action of the two insecticides. The effects of blood from the poisoned insects on the electrical activity of the isolated nerve cord of roaches are discussed in relation to the penetration of the nerve cord by known neurohumors.


Sign in / Sign up

Export Citation Format

Share Document