TY - JOUR
T1 - Administration of 8-hydroxy-2-(di-n-propylamino)tetralin in raphe nuclei dorsalis and medianus reduces serotonin synthesis in the rat brain
T2 - Differences in potency and regional sensitivity
AU - Invernizzi, R.
AU - Carli, M.
AU - Di Clemente, A.
AU - Samanin, R.
PY - 1991
Y1 - 1991
N2 - Following administration of 8-hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT; 0.04-5.0 μg/0.5 μl) in the raphe nucleus dorsalis (DR) or medianus (MR), the synthesis of serotonin (5-HT), as assessed by the accumulation of 5-hydroxytryptophan (5-HTP) after decarboxylase inhibition, was measured in various regions of the rat CNS. At all doses, 8-OH-DPAT in the DR significantly reduced 5-HTP accumulation in the striatum, nucleus accumbens, cortex, and prefrontal cortex, whereas even the highest dose had no effect in the hippocampus, hypothalamus, and spinal cord. One microgram of 8-OH-DPAT in the MR significantly reduced 5-HTP accumulation in the nucleus accumbens and prefrontal cortex, and 5 μg had an effect in all the areas except the striatum and spinal cord. One and 5 μg of 8-OH-DPAT, administered in either the DR or MR, did not significantly modify the accumulation of dihydroxyphenylalanine in the striatum and nucleus accumbens. The results confirm that DR and MR have different sensitivities to 5-HT(1A) receptor agonists, and that activation of 5-HT(1A) receptors in these nuclei produces different effects on 5-HT synthesis in different brain regions.
AB - Following administration of 8-hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT; 0.04-5.0 μg/0.5 μl) in the raphe nucleus dorsalis (DR) or medianus (MR), the synthesis of serotonin (5-HT), as assessed by the accumulation of 5-hydroxytryptophan (5-HTP) after decarboxylase inhibition, was measured in various regions of the rat CNS. At all doses, 8-OH-DPAT in the DR significantly reduced 5-HTP accumulation in the striatum, nucleus accumbens, cortex, and prefrontal cortex, whereas even the highest dose had no effect in the hippocampus, hypothalamus, and spinal cord. One microgram of 8-OH-DPAT in the MR significantly reduced 5-HTP accumulation in the nucleus accumbens and prefrontal cortex, and 5 μg had an effect in all the areas except the striatum and spinal cord. One and 5 μg of 8-OH-DPAT, administered in either the DR or MR, did not significantly modify the accumulation of dihydroxyphenylalanine in the striatum and nucleus accumbens. The results confirm that DR and MR have different sensitivities to 5-HT(1A) receptor agonists, and that activation of 5-HT(1A) receptors in these nuclei produces different effects on 5-HT synthesis in different brain regions.
KW - Dopamine synthesis
KW - Raphe nuclei
KW - Rat brain
KW - Serotonin 5-HT(1A) receptors
KW - Serotonin synthesis
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U2 - 10.1111/j.1471-4159.1991.tb02587.x
DO - 10.1111/j.1471-4159.1991.tb02587.x
M3 - Article
C2 - 1824782
AN - SCOPUS:0026085789
VL - 56
SP - 243
EP - 247
JO - Journal of Neurochemistry
JF - Journal of Neurochemistry
SN - 0022-3042
IS - 1
ER -