TY - JOUR
T1 - The effect of serotonergic and dopaminergic lesions on sodium-sensitive [3H]mazindol binding in rat hypothalamus and corpus striatum
AU - Angel, Itzchak
AU - Janowsky, Aaron
AU - Paul, Steven M.
PY - 1989/12/4
Y1 - 1989/12/4
N2 - The effects of intracerebroventricular administration of 6-hydroxydopamine (6-OHDA) and 5,7-dihydroxytryptamine (5,7-DHT) on sodium-sensitive [3H]mazindol binding were investigated in the rat hypothalamus and corpus striatum. In the hypothalamus, specific [3H]mazindol binding was inhibited by low concentrations of sodium and stimulated by high-sodium concentrations, whereas in the corpus striatum, only a sodium-dependent stimulation of [3H]mazindol binding was observed. Lesions with 6-OHDA significantly reduced sodium-dependent [3H]mazindol binding in the corpus striatum, but had no effect on the binding of [3H]mazindol in the absence of sodium. Lesions of serotonergic neurons with 5,7-DHT, however, had no effect on [3H]mazindol binding in the striatum, but resulted in a significant increase in the number of [3H]mazindol binding sites in the hypothalamus. These data suggest that [3H]mazindol may bind to two anatomically distinct binding sites, one that is stimulated and the other inhibited by sodium. The sodium-stimulated binding sites appear to be located on dopaminergic terminals in the striatum, and in the hypothalamus, the sodium-inhibited sites appear to be regulated by serotonergic neuronal activity.
AB - The effects of intracerebroventricular administration of 6-hydroxydopamine (6-OHDA) and 5,7-dihydroxytryptamine (5,7-DHT) on sodium-sensitive [3H]mazindol binding were investigated in the rat hypothalamus and corpus striatum. In the hypothalamus, specific [3H]mazindol binding was inhibited by low concentrations of sodium and stimulated by high-sodium concentrations, whereas in the corpus striatum, only a sodium-dependent stimulation of [3H]mazindol binding was observed. Lesions with 6-OHDA significantly reduced sodium-dependent [3H]mazindol binding in the corpus striatum, but had no effect on the binding of [3H]mazindol in the absence of sodium. Lesions of serotonergic neurons with 5,7-DHT, however, had no effect on [3H]mazindol binding in the striatum, but resulted in a significant increase in the number of [3H]mazindol binding sites in the hypothalamus. These data suggest that [3H]mazindol may bind to two anatomically distinct binding sites, one that is stimulated and the other inhibited by sodium. The sodium-stimulated binding sites appear to be located on dopaminergic terminals in the striatum, and in the hypothalamus, the sodium-inhibited sites appear to be regulated by serotonergic neuronal activity.
KW - 5,7-Dihydroxytryptamine
KW - 6-Hydroxydopamine
KW - Corpus striatum
KW - Hypothalamus
KW - Mazindol, [H]-binding
UR - http://www.scopus.com/inward/record.url?scp=0024385163&partnerID=8YFLogxK
U2 - 10.1016/0006-8993(89)91687-9
DO - 10.1016/0006-8993(89)91687-9
M3 - Article
C2 - 2514010
AN - SCOPUS:0024385163
SN - 0006-8993
VL - 503
SP - 339
EP - 341
JO - Brain Research
JF - Brain Research
IS - 2
ER -