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SOME PHYSIOLOGICAL ACTIONS OF CYANIDES.
1Zoological Laboratory of the University of Pennsylvania, Philadelphia.
The Journal of General Physiology
|October 30, 2009
Summary
Hydrogen cyanide (HCN) affects cells by penetrating them easily and causing acidity. Protozoan resistance to HCN varies by species and resembles resistance to CO2 and H2S.
Area of Science:
- Biochemistry
- Toxicology
- Cell Biology
Background:
- Hydrogen cyanide (HCN) and its salts exhibit significant physiological effects.
- Understanding the mechanisms of HCN toxicity is crucial for various biological and toxicological applications.
Purpose of the Study:
- To elucidate the physiological actions of hydrogen cyanide (HCN) and its salts at the cellular level.
- To investigate the differential resistance of protozoan species to HCN exposure.
Main Methods:
- Analysis of HCN's molecular penetration into living cells.
- Observation of cellular response to HCN in varying pH conditions (acidic, neutral, alkaline).
- Comparative studies of protozoan resistance to HCN, CO2, H2S, and mineral acids.
Main Results:
- HCN's action is attributed to easy cell penetration, ionization into H+ and CN- ions, its weak acid properties allowing free molecules, and specific chemical activity.
- HCN induces intracellular acidity due to rapid molecular penetration, regardless of external pH.
- Protozoan resistance order to HCN mirrors that of CO2 and H2S but is inverse to mineral acids.
- Specific species of Paramecia exhibit distinct resistance levels to HCN, with P. caudatum being most resistant and P. bursaria least.
Conclusions:
- HCN exerts physiological effects through cellular penetration and ionization, modulated by its weak acid nature.
- HCN's ability to induce intracellular acidity is a key toxicological mechanism.
- Differential susceptibility of protozoan species to HCN highlights species-specific toxicological responses.
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