The role of the heat stress response in the tolerance of immature
renal tubules to anoxia.
Gaudio, Karen M., Gunilla Thulin, Andrea Mann, Michael Kashgarian,
Norman J. Siegel.
Departments of Pediatrics and Pathology, Yale University School of
Medicine, New Haven, Connecticut
APStracts 5:0040F, 1998.
The stress response was studied in suspensions of tubules from
immature (IT) and mature (MT) rats after noninjury, heat, oxygen and
anoxia. Under all conditions, IT exhibited more exuberant activation
of heat shock transcription factor (HSF) than MT. Characterization of
activated HSF in immature cortex revealed HSF1. Also, 2 hours after
each condition, HSP-72 mRNA was 2-fold in IT. The metabolic response
to 45 minutes anoxia, 20 minutes reoxygenation was assessed by
measuring O2 consumption (O2) Basal O2C was manipulated with ouabain,
nystatin, CCCP. Basal O2C in IT were half the value of MT. Following
anoxia, basal O2C was reduced by a greater degree in MT. Ouabain
reduced O2C to half the basal value in both noninjured and anoxic
groups. Basal O2C was significantly stimulated by nystatin but not to
the same level following anoxia in MT and IT. Basal O2C was also
stimulated by CCCP but after anoxia, CCCP O2C was significantly less
in MT with no decrease in IT suggesting mitochondria are better
preserved in IT. Also, O2C devoted to nontransport activity was
better maintained in IT.
Received 10 June 1997; accepted in final form 12 February 1998.
APS Manuscript Number F187-7.
Article publication pending Am. J. Physiol. (Renal Physiology).
ISSN 1080-4757 Copyright 1998 The American Physiological Society.
Published in APStracts on 19 February 1998