Pangerl A, Pangerl B, Reiter R J, Vaughan G M, Jones D J
Department of Cellular and Structural Biology, University of Texas Health Science Center, San Antonio 78284.
Brain Res. 1989 Jun 19;490(1):166-9. doi: 10.1016/0006-8993(89)90445-9.
Specific binding of [125I]iodo-[beta-(4-hydroxyphenyl)-ethylaminomethyl]tetralone ([ 125I]HEAT) was used to assess alpha 1-adrenergic receptors on pineal gland membranes of male Syrian hamsters (Mesocricetus auratus) housed under a 14:10 h light-dark cycle (lights on at 06.00 h). Saturation experiments with pooled pineal membrane preparations showed the presence of alpha 1-adrenergic receptor sites (dissociation constant Kd approx. 0.1 nM). Analysis of 4 time points indicated no significant change in Kd, but significant (P less than 0.01) changes of receptor density (Bmax) with a minimum recorded at night. Binding of a constant amount of [125I]HEAT (200 pM) to pineal membranes at 8 time points exhibited a circadian variation (P less than 0.001) of receptor density with lowest values around midnight and highest levels during daytime.
采用[125I]碘代-[β-(4-羟基苯基)-乙胺基甲基]四氢萘酮（[125I]HEAT）的特异性结合来评估处于14:10小时明暗循环（06:00开灯）饲养条件下的雄性叙利亚仓鼠（金仓鼠）松果体膜上的α1-肾上腺素能受体。对合并的松果体膜制剂进行的饱和实验显示存在α1-肾上腺素能受体位点（解离常数Kd约为0.1 nM）。对4个时间点的分析表明Kd无显著变化，但受体密度（Bmax）有显著（P<0.01）变化，夜间记录到最低值。在8个时间点用恒定剂量（200 pM）的[125I]HEAT与松果体膜结合，显示受体密度呈昼夜变化（P<0.001），午夜左右值最低，白天最高。
