INVESTIGADORES
BREGONZIO DIAZ Claudia
artículos
Título:
Turnover rate and stimulus-evoked release of dopamine by progesterone and N-methyl-D-aspartic acid in rat striatum during pregnancy
Autor/es:
CABRERA, R.J. AND BREGONZIO, C
Revista:
EUROPEAN JOURNAL OF PHARMACOLOGY
Referencias:
Año: 1996 vol. 317 p. 55 - 59
ISSN:
0014-2999
Resumen:
The proposed modulatory role of progesterone on dopaminergic nerve terminal
activity in the striatum was examined in pregnant rats. Endogenous dopamine
concentration and the in vitro effect of exogenous progesterone in association
with N-methyl-D-aspartic acid (NMDA) upon [3H]dopamine release from striatal
slices were determined. Striatal dopamine and 3,4-dihidroxyphenylacetic acid
(Dopac) contents on day 5 of pregnancy were significantly higher than those
found at the other stages of pregnancy and proestrus. On days 5 and 15 of
pregnancy, progesterone (400 nM) was able to enhance [3H]dopamine release
stimulated by NMDA (50 microM). A similar effect was found in striatal slices
from proestrus rats. In contrast, progesterone was without an effect on days 1,
10 and 20 of pregnancy and postpartum. The results suggest that an increased
synthesis and/or release of dopamine takes place on certain days of pregnancy
and, simultaneously, that there is a significant increase in the responsiveness
of striatal dopaminergic nerve terminals to excitatory inputs. They provide
further support for a modulatory role of progesterone in relation with a
glutamatergic action on dopaminergic activity in the corpus striatum.