Inoue O, Akimoto Y, Hashimoto K, Yamasaki T
Int J Nucl Med Biol. 1985;12(5):369-74.
The biodistribution of [3H]Ro 15-1788 in control and stress-loaded mice (forced swimming) was compared. In control mice, carrier-free [3H]Ro 15-1788 was selectively and highly distributed in Bz receptor rich brain regions, while radioactivity in the brain was very low following administration of carrier-added tracer, which suggested that in vivo non-specific binding of this tracer was very low. Significant changes in biodistribution of carrier-free [3H]Ro 15-1788 were observed in stress-loaded mice, which strongly indicated that in vivo binding availability of Bz receptor in the brain was rapidly and reversibly reduced by acute stress. The degree of these changes was very dependent upon the stressful conditions, such as swimming duration and water temperature, and a significant alteration in biodistribution of [3H]Ro 15-1788 was particularly observed in the cerebral cortex. Simplified Scatchard analysis of in vivo binding of this tracer was performed, and results suggested that these alterations were mainly caused by changes in the Kd value rather than the Bmax value.
比较了[3H]Ro 15-1788在对照小鼠和应激（强迫游泳）小鼠体内的生物分布。在对照小鼠中，无载体的[3H]Ro 15-1788选择性且高度分布于富含苯二氮䓬（Bz）受体的脑区，而给予加载体示踪剂后脑中放射性很低，这表明该示踪剂的体内非特异性结合非常低。在应激小鼠中观察到无载体的[3H]Ro 15-1788生物分布有显著变化，这强烈表明急性应激可使脑中Bz受体的体内结合可用性迅速且可逆地降低。这些变化的程度非常依赖于应激条件，如游泳持续时间和水温，并且在大脑皮层中特别观察到[3H]Ro 15-1788生物分布有显著改变。对该示踪剂的体内结合进行了简化的Scatchard分析，结果表明这些改变主要是由解离常数（Kd）值而非最大结合容量（Bmax）值的变化引起的。
