Abstract
Purpose::
to quantify the concentration of heat shock proteins in lenses and culture medium in organ culture at elevated temperatures.
Methods::
Pig lenses obtained from a local abattoir were dissected aseptically and incubated in medium M199 without serum for 4 days to stabilize, and those with protein leakage less than 10 mg/L were taken for heat shock. Heat shock was performed by incubation for 1 hr in M199 wthout serum at a variety of temperatures from 37C to 55C. After incubation for 24 hr., the tissue culture medium was desalted and concentrated, and the lenses weighed and homogenized. The medium and homogenates were analysed for HSP 70 and HSP 27 by western blotting. ScantoxTM and Scion Image analysis of lens photographs were used to estimate cataract image blurring.
Results::
Heat shock proteins were increased in concentration in the culture medium after heat shock at 45C. A temperatures up to 48 C the concentration of HSPs in the culture medium increased, but at 55 C no increase in concentration was found. Differences in the relative behavior of Hsp 70 and Hsp27 were found. The degree of cataract blurring of the images also increased, while the percent differences in lens weights decreased with increasing temperature.
Conclusions::
This is the first description of Heat Shock Protein release by the lens. The heat shock protein concentration in the lens, its release, and degradation of the image quality all occurred as the temperature increased . The heat shock proteins may play a protective role in the eye lens when the eye is exposed to ambient temperatures as high as 55 or 60C in nature, or ionizing radiation.
Keywords: pathology: experimental • cataract • stress response