Physiological Responses of the Antarctic Green Alga Prasiola crispa ssp. antarctica to Salinity Stress

Foi levada a efeito um estudo sobre a sensibilidade do peixe antártico Notothenia neglecta ao agente anticolinesterásico não poluente Malathion [O-O-dimetil S-(1,2-dicarbetoxietil) fosforoditioato]. Especimens de N. neglecta foram injetados com Malathion em doses de 15 ou 30 mg/kg de peso corpóreo e observados durante dez dias. O experimento foi monitorado pela determinação da atividade anticolinesterásica sérica bem como pela observação da depressão respiratória, pelo comportamento catatônico dos animais, pela mudança da coloração corpórea e pelas respostas colinérgicas muscarínicas. Os resultados desse experimento mostraram que a N. neglecta é significantemente mais sensível ao Malathion do que o peixe de água doce Oreochomis niloticus. Ao final do experimento todo o material utilizado foi cuidadosamente embalado e transportado para nossos laboratórios no Brasil. Abstract A research has been carried out on the sensitivity of the Antarctic fish Notothenia neglecta towards the non-pollutant anticholinesterase agent Malathion [O,O-dimethyl S-(1,2-dicarbethoxyethyl) phosphorodithioate]. Specimens of N. neglecta were injected with Malathion in doses of 15 or 30 mg/kgbw and observed regarding their behavior, somatic and physiological responses during ten days. They were monitored by the assay of serum cholinesterase activity as well as by the observation of respiratory depression and by the catatonic behavior, changes of body color and cholinergic muscarinic responses. Results of this experiment showed that N. neglecta is significantly more sensitive to Malathion as compared to the fresh water fish Oreochomis niloticus. At the end of the experiment all waste material was packed up and carried to our laboratories back home.

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Physiological reactions to cold of men in the Antarctic

Journal of Applied Physiology ◽

10.1152/jappl.1964.19.4.593 ◽

1964 ◽

Vol 19 (4) ◽

pp. 593-597 ◽

Cited By ~ 19

Author(s):

C. H. Wyndham ◽

R. Plotkin ◽

A. Munro

Keyword(s):

South African ◽

Cold Adaptation ◽

Physiological Responses ◽

Control Group ◽

Climatic Chamber ◽

Thermoneutral Zone ◽

The Antarctic ◽

Physiological Reactions ◽

Average Skin ◽

Skin Temperatures

The physiological reactions to cold of five members of the 1961–1962 South African expedition to the Antarctic were studied in a climatic chamber in Johannesburg, and again after 6 months and after 12 months in the Antarctic. Their results were compared with the results of a control group in Johannesburg. The predeparture results were within the 95% significance intervals of the control group. After 12 months in the Antarctic their results fell outside the 95% significance intervals of the control group when at 5 C air temperature, metabolism, average skin temperatures, rectal temperatures, and finger temperatures were all significantly lower. Toe temperatures, however, were higher. There appeared to be a gradual “adaptation” and general “toughening” to the cold, because the subjects shed their clothing progressively until they could run about naked in the snow. The values at the thermoneutral zone of 27 C did not change over the 12 months, however. It is therefore concluded that it is unlikely that the changes in physiological responses were of endocrine origin. cold adaptation in Antarctic; metabolic and body temperature reactions to cold Submitted on August 16, 1963

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