Ultrastructural changes in sarcosomes after exposure of adult Calliphora erythrocephala to lethal and sub‐lethal high temperatures

The effects of lethal and sub‐lethal high temperatures on the morphology of intact flight muscle sarcosomes of adult Calliphora erythrocephala are described. Treatment of adult flies to lethal temperatures results in ultrastructural changes in the organisation of the cristae and the appearance of electron opaque inclusions. These changes have not been observed after sub‐lethal heat treatment, when 50% of the animals recover. It is suggested that changes in the ultrastructure of the intact sarcosomes may be correlated with changes in their ability to couple oxidative phosphorylation with α‐glycerophosphate. Age‐dependent changes in the sensitivity of sarcosomes are related to changes in the heat death point of the animal and suggest that the impairment of sarcosomal function may be one of the primary lesions in heat death of adult C. erythrocephala .