Author(s):
Geraldo, A.C.A.P.M.
; Oliveira, L.J.
; Pereira, A.M.F.
; Moreira da Silva, F.
; Titto, E.A.L.
Date: 2013
Persistent ID: http://hdl.handle.net/10174/9374
Origin: Repositório Científico da Universidade de Évora
Subject(s): HSPA1A; heat stress; cows; HSP90AA1
Description
The main purpose for this study was the quantification of the heat shock proteins HSPA1A and HSP90AA1, in cow lymphocytes, when subjected to heat stress directly - in vivo, or indirectly - in vitro. The aim was to identify differences between HSP expression in vitro and in vivo. The experiment was conducted in the Biometeorology and Ethology Laboratory of FZEA-USP. Were used three female Holstein Frisian, which were subjected to heat stress, by sun exposure. The blood samples were collected after sun exposure, with a temperature of 40 ± 2 º C, during three days. For in vitro tests, blood of the same animals was collected and placed for a period of 4 hours in a water bath at 40 º C, thus simulating the thermal stress. Total RNA of lymphocytes was extracted, treated with DNase I and submitted to cDNA synthesis for gene expression quantification of HSPA1A and HSP90AA1, by real time PCR (qRT-PCR). The data were tested for normality by Kolmogorov-Smirnov test and for homocedasticity by Levene test. Data were analyzed according to a general linear model procedure with 2 fixed factors treatment and genes expression. Significantly different means were submitted to post-hoc comparisons of means (LSD test) and regarded as significantly different when P<0.05. The results showed that there are no significant differences between the in vitro and the in vivo treatments,