Temporal variation in constitutive and inducible heat shock proteins in the Zebra Finch Taeniopygia guttata

Cellular stressors initiate the heat shock response mediated by heat shock proteins (HSPs). There are two main types of HSPs, constitutive (always expressed) and inducible (upon stress), but as many in vivo studies fail to distinguish between them and because temporal expression patterns often differ among various types of HSPs, it is unclear when to measure HSPs. In this study, 26 (13 per treatment) adult female Zebra Finches Taeniopygia guttata were heat‐stressed (39 °C) or placed in a control brooder (room temperature) for 3 h and were bled 1 week prior to and at 1, 2, 4, 6 and 20 h post‐treatment. Treatment had no effect on levels of either constitutive HSP70 or inducible HSP90, but both HSPs decreased with time relative to baseline, suggesting a possible effect of handling stress and/or circadian variation.