Estrogen administration increases neuronal responses to excitatory amino acids as a long-term effect

Ongoing studies from this laboratory have demonstrated marked potentiating actions of the sex steroid 17β-estradiol (E₂) on glutamate-induced excitation. In the present study, systemic injection of a physiological dose fo E₂ was demonstrated to augment significantly excitatory responses of cerebellar Purkinje (Pnj) cells to iontophoretic application of the specific excitatory amino acid (e.a.a.) agonists quisqualate and N-methyl-d-aspartate. Potentiation of e.a.a. responses was observed as rapidly as 5-10 min post E₂, and was, in many cases, a persistent, non-decremental effect. These observed long-term actions of E₂ may provide one mechanism for the activating effects of the steroid on sensorimotor function and acitivity.