Increased number of brain benzodiazepine receptors after in-vivo administration of estazolam to rats

Estazolam significantly increaed the K(d) of [³H]flunitrazepam in-vitro, like other benzodiazepines (BDZs) acting competitively at the receptor site. At variance with other BDZs, estazolam significantly raised the B(max) for [³H]flunitrazepam, at concentrations lower than its K(i) for BDZ receptors. This effect may be responsible for the observed increase in [³H]diazepam binding after in-vivo administration of estazolam to rats.