Autor: |
A N, Martins, M V, Blom, A M, Reis, C C, Coimbra |
Rok vydání: |
1991 |
Předmět: |
|
Zdroj: |
Brazilian journal of medical and biological research = Revista brasileira de pesquisas medicas e biologicas. 24(11) |
ISSN: |
0100-879X |
Popis: |
The cold-adaptation process was examined in preoptic-lesioned (PO, 18 rats) and adrenaldemedullated-preoptic-lesioned rats (ADPO, 16 rats). PO rats and ADPO female Wistar rats were cold acclimatized to 5 degrees C for 2 operated and then treated exactly like the lesioned rats. Lesions in the PO region caused a decrease in the ability to maintain normal body temperature in a cold environment (5 degrees C for 2 h). Their colonic temperature fell even by the end of the 2nd h of cold exposure (-1.1 degrees C for PO rats and -1.25 degrees C for ADPO rats, P less than 0.01). However, after 2 weeks of cold acclimation the PO rats, but not the ADPO rats were able to thermoregulate in the cold and showed a normal increase in interscapular brown adipose tissue weight (79%, P less than 0.01). These data suggest that the PO is not an essential link for cold adaptation when a mild cold-adaptation method is used. Furthermore, the data show that increased adrenal medullary activity is required for the cold adaptation process in PO rats. |
Databáze: |
OpenAIRE |
Externí odkaz: |
|