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F Fadda

Publications and source records attributed to F Fadda.

At least 73 records · Page 4Linked to original sources
PubMed1980

Effect of acute and chronic ethanol on dopamine synthesis in the caudate nucleus, substantia nigra and frontal cortex.

A single oral administration of 3.2 g/kg ethanol to normal rats increased 3,4-dihydroxyphenylacetic acid (DOPAC) content and DOPA formation in the caudate nucleus but had no effect in frontal cortex and substantia nigra and did not modify dopamine (DA) levels in any of the brain regions analyzed. Complete tolerance to the stimulant effect on DOPA formation developed after chronic ethanol-treatment (3.2 g/kg daily for 60 days). However ethanol administration to ethanol dependent rats produces a marked DA depletion and increases DOPAC concentration in the brain areas studied. The present results show that acute and chronic ethanol release DA stores, but only in the acute conditions DA depletion is compensated by enhanced synthesis.

3,4-Dihydroxyphenylacetic Acid↗
PubMed1980

Effect of ethanol on the metabolism of regional brain dopamine.

Acute oral administration of ethanol (3.2g/kg) to rats increased (DOPAC) levels in the caudate nucleus, but had no effect on DOPAC levels in the substantia nigra and frontal cortex and failed to modify dopamine content in any of the above areas. On the other hand, the administration of the same dose of ethanol to rats which had been chronically treated with ethanol (3.2g/kg daily for 60 days), produced a decrease of DA content and a parallel increase of DOPAC levels in all areas studied. In chronically treated rats, 24 hrs after last ethanol administration dopamine levels in the frontal cortex were 60% higher than in controls. The results suggest that ethanol administration causes dopamine release in different brain areas.

3,4-Dihydroxyphenylacetic Acid↗
PubMed1980

Effects of tiapride on homovanillic acid levels in human cerebrospinal fluid drawn at pneumoencephalography.

The effect of tiapride on HVA and 5-HIAA levels in the CSF drawn at pneumoencephalography (PEG) was studied. Five consecutive 5 ml fractions of CSF were drawn from control and tiapride-treated subjects. In both groups, a linear increase in HVA concentrations was found between the first and subsequent fractions. On the contrary, no significant difference in 5-HIAA concentrations was found in sequential CSF samples. Tiapride increased the mean HVA concentrations and caused a steeper caudocranial gradient of this metabolite but failed to modify 5-HIAA concentrations. The results suggest that tiapride blocks dopamine (DA) receptors and increases DA synthesis.

Adult↗
PubMed1979

Release of dopamine in the ventral tegmental area of rat.

In this preliminary report we showed that 3,4-dihydroxyphenylacetic acid (DOPAC), the major metabolite of dopamine (DA), is present in the ventral tegmental area. This finding indicates that in the ventral tegmental area, which contains the cell bodies of dopaminergic neurons of the mesocortical and mesolimbic DA systems, DA may be released by a mechanism similar to that operating in the nerve endings. However, haloperidol, which increases DOPAC levels in the substantia nigra, failed to do so in the ventral tegmental area. The results support the contention that DA neurons in the ventral tegmental area have distinctive features from nigral DA neurones.

3,4-Dihydroxyphenylacetic Acid↗
PubMed1979

Foot-shock stress accelerates non-striatal dopamine synthesis without activating tyrosine hydroxylase.

Electric foot-shock stress (20 min) increases DOPAC content in the frontal cortex (by about 80%) and in the nucleus accumbens (by 35%) but not in the striatum. However, foot shock stress failed to modify the kinetic properties of tyrosine hydroxylase (Vmax, Km for DMPH4 cofactor) in any of the above areas. Similar results were obtained in rats in which noradrenergic terminals in the n. accumbens and in the frontal cortex had been eliminated by injection of 6-OH-dopamine into the ascending dorsal noradrenergic bundle. The results support the hypothesis that limbic and cortical DA is involved in emotional states and indicate that DA synthesis may be regulated independently from changes in the kinetics properties of tyrosine hydroxylase.

3,4-Dihydroxyphenylacetic Acid↗
PubMed1978

A radioenzymatic method to measure picogram amounts of dopamine and 3,4-dihydroxyphenylacetic acid (DOPAC) in small samples of brain tissue.

A radioenzymatic method for simultaneous determination of dopamine and DOPAC in small brain areas is described. By using this assay, 250 pg of dopamine and 150 pg of DOPAC can be estimated. The present method has been applied to compare the effect of different psychotropic drugs on the dopamine and DOPAC levels in the caudate nucleus, substantia nigra and medial basal hypothalamus.

3,4-Dihydroxyphenylacetic Acid↗