Autoradiographic Changes in Central Benzodiazepine Binding Sites and Their Coupling to γ-Aminobutyric Acid Receptors after Seizures in the Developing Rat

Abstract

ABSTRACT. Benzodiazepines are psychoactive substances classically used for their anticonvulsant properties in neonates as well as in adults. In a previous work, we have shown that seizures lead to an age-dependent upregulation of central benzodiazepine binding sites measured in isolated rat cerebral membranes. However, information concerning regional changes in the receptor density was lacking. In our present study, the effects of bicuculline- GABA, y-aminobutyric acidNumerous neuropathologic studies have pointed out that during the neonatal period and early infancy, epileptic manifestations are relatively frequent, with peculiar characteristics. Children are more susceptible to epileptic brain damage than adults (I), and recurrent or prolonged seizures in infants and children may be followed by major neurologic sequelae (2).Benzodiazepines are psychoactive drugs with anxiolytic, anticonvulsant, and muscle relaxant properties that are widely prescribed in neonates as well as in adults (3). The mechanism of benzodiazepine central action has been attributed to a highaffinity, saturable, and specific binding site and its interaction with a GABA-regulated chloride channel (4, 5). In animals,