Investigation on the thermostability of XXXX hormone receptors in lyophilized @entity291 uterine tissue powder.

@entity172 @entity53 @entity134 @entity342 @entity230 @entity291
Powdered @entity291 uteri were lyophilized and sealed in a vacuum. The effects of lyophilization and the thermostability of the binding activity of uterine @entity134 hormone receptors were studied. The lyophilized powder was analyzed for its ability to bind @entity172 , progestin, @entity342 , and glucocorticoid @entity230 . Lyophilization had no deleterious effects on the binding activity. Storage of the lyophilized powder at +20 C for more than 14 days did not reduce the binding activity. No reduction of the binding capacity was also observed when the storage temperature was at +30 C for 16 hours. However, a slight loss of specific binding sites was observed for @entity53 (-12%) at the storage temperature of +40 C, but the other @entity134 binding proteins were more stable. When the storage temperature was at +60 C for 16 hours, a loss of about 24% was observed for the specific @entity172 binding sites, whereas the binding capacity of progestin, @entity342 , and glucocorticoid receptors was reduced by only less than 10%. Storage at the high temperature of +80 C for 16 hours resulted in a loss of only 36% for the @entity172 binding capacity and less than 30% loss for the other binding proteins. The freeze-dried uterine powders can be useful quality control specimens for @entity134 receptor assays.
