Experimentally induced heat- and cold-shock tolerance in adult Panstrongylus megistus (Burmeister) (Hemiptera, Reduviidae)
Braz. j. biol
; 63(3): 449-455, Aug. 2003. ilus
Artigo
em Inglês
| LILACS
| ID: lil-353967
Biblioteca responsável:
BR1.1
RESUMO
The survival rate of domestic male and female adult Panstrongylus megistus was studied after sequential heat and cold shocks in order to investigate shock tolerance compared to that previously reported for nymphs. Sequential shocks were such that a milder shock (0ºC, 5ºC, 35ºC, or 40ºC for 1 h) preceded a severe one (0ºC or 40ºC for 12 h), separated by intervals of 8, 18, 24, and 72 h at 28ºC (control temperature). The preliminary thermal shock induced tolerance to the more severe one, although tolerance intensity depended on the initial shock temperature and the interval between treatments. Despite the observed tolerance, the survival rate for insects subjected to both shocks decreased when compared to that of individuals subjected to a single mild shock. When tolerance differed with sex, females showed greater values than males. In contrast to the response detected in nymphs, for which higher heat tolerance values were sustained for intervals of up to 24 h (preliminary shock, 35ºC) or even longer (preliminary shock, 40ºC) between sequential shocks, significant values were verified in adults only for shock intervals of up to 8 h (preliminary shock, 40ºC). While findings for nymphs exhibited considerable cold-shock tolerance under conditions in which preliminary shocks were given at 5ºC or 0ºC and the periods between shocks were up to 72 h long, the adults were shown to be capable of acquiring a substancial tolerance response to a more severe cold shock only when the preliminary shock was given at 0ºC and shock interval surpassed 18 h. It is assumed that the mechanisms involved in the cellular protection of P. megistus under sequential temperature shocks (heat shock protein action?) may loose effectiveness with insect development.
Texto completo:
Disponível
Coleções:
Bases de dados internacionais
Base de dados:
LILACS
Assunto principal:
Panstrongylus
/
Regulação da Temperatura Corporal
/
Temperatura Baixa
/
Resposta ao Choque Térmico
/
Temperatura Alta
Limite:
Animais
Idioma:
Inglês
Revista:
Braz. j. biol
Assunto da revista:
Biologia
Ano de publicação:
2003
Tipo de documento:
Artigo
/
Documento de projeto
País de afiliação:
Brasil
Instituição/País de afiliação:
Sucen/BR
/
Universidade Estadual de Campinas/BR