Discriminative stimulus properties of estradiol in male and female rats revealed by a taste-aversion procedure.
Gonadectomized male and female rats were trained to discriminate 50µg/kg estradiol-17B(E(2)) from its vehicle in a one-bottle forced-drinking discriminative taste-aversion procedure. The animals were injected SC with E(2) or arachidic oil, 60min prior to daily training sessions during which they had access to a saccharin (Sac) solution for 10min. Animals injected with E(2) prior to Sac-LiCl pairings and with arachidic oil prior to Sac-NaCl pairings acquired hormone discrimination, only suppressing Sac intake following the administration of E(2) and not following the administration of arachidic oil. Both males and females reliably discriminated E(2) from arachidic oil within 28 training sessions. Subsequent generalization tests revealed dose-dependent stimulus control of Sac intake by E(2) in both sexes (range of substitution doses: 0.4-250µg/kg). The results show that E(2) may act as a discriminative stimulus in male and female rats.
Netherlands Institute for Brain Research, Meibergdreef 33, 1105 AZ Amsterdam, The Netherlands State University of Utrecht, Faculty of Pharmacy, Sorbonnelaan 16, 3584 CA Utrecht, The Netherlands.
R.
R
de Beun
R.P.W.
RP
Heinsbroek
J.L.
JL
Slangen
N.E.
NE
van De Poll