Search Results - (Author, Cooperation:U. Spampinato)

2014-01-05

American Association for the Advancement of Science (AAAS)

0036-8075

1095-9203

Biology

Chemistry and Pharmacology

Computer Science

Medicine

Natural Sciences in General

Physics

Animals ; Brain/*drug effects/metabolism ; Cannabinoid Receptor Antagonists/administration & dosage ; Cannabis/*toxicity ; Dronabinol/*toxicity ; Male ; Marijuana Abuse/drug therapy ; Mice ; Mice, Inbred C57BL ; Pregnenolone/*administration & dosage/*metabolism ; Rats ; Rats, Sprague-Dawley ; Rats, Wistar ; Receptor, Cannabinoid, CB1/*agonists/*antagonists & inhibitors

1471-4159

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

Abstract: The effects of 5-methoxy-N, N-dimethyltryptamine (5-MeO-DMT) and m-chlorophenylpiperazine (CPP), two 5-hydroxytryptamine (5-HT, serotonin) agonists, on the accumulation of 3,4-dihydroxyphenylalanine (DOPA) were studied in the striatum of rats treated with γ-butyrolactone (GBL). Unlike 2 mg/kg i.p. apomorphine, neither 5 mg/kg i.p. 5-MeO-DMT nor 2.5 mg/kg i.p. CPP significantly reduced the GBL-induced increase in DOPA accumulation in the striatum. 5-MeODMT and CPP significantly reduced DOPA accumulation in animals that had received the aromatic amino acid decarboxylase inhibitor Ro 4–4602 but not GBL. 5-HT (10 μg in 0.5 μl) injected in the substantia nigra, pars compacta, like GBL, significantly increased Ro 4-4602-induced accumulation of DOPA in the striatum. The data indicate that 5-HT agonists can reduce 3,4-dihydroxyphenylethylamine (DA, dopamine) synthesis in the striatum of rats only when the impulse flow of DA neurons is intact. An indirect effect through mechanisms controlling DA synthesis in the striatum, for instance cholinergic and GABA-ergic neurons, is suggested.

Electronic Resource

1749-6632

Blackwell Publishing Journal Backfiles 1879-2005

Natural Sciences in General

Electronic Resource

1432-2072

Key words Microdialysis ; Haloperidol ; 8-OH-DPAT ; Ritanserin ; Catalepsy ; Dopamine ; Serotonin ; Striatum

Springer Online Journal Archives 1860-2000

Medicine

Abstract In this study, both catalepsy and changes in extracellular levels of striatal dopamine (DA) and dihydroxyphenyl acetic acid (DOPAC) induced by the typical neuroleptic haloperidol (HAL) were simultaneously assessed, using intracerebral microdialysis in freely moving rats, in the presence of either the 5-HT1A agonist 8-OH-DPAT or the 5-HT2A/C antagonist ritanserin. HAL (1 mg/kg, SC) elicited a strong cataleptic state, reaching its maximal intensity (about 240 s) 2 h after the drug administration. This effect was paralleled by a long-lasting enhancement of striatal DA and DOPAC extracellular levels, reaching 230 and 350% of basal values, respectively. 8-OH-DPAT (0.1 mg/kg, SC) given 2.5 h after, and ritanserin (0.63 and 1.25 mg/kg, IP), given 15 min prior to HAL, significantly reduced the neuroleptic-induced catalepsy. However, both 5-HT agents failed to modify basal DA and DOPAC striatal outflow as well as the stimulatory effect of HAL on these parameters. It can thus be concluded that the anticataleptic effect of these compounds is not related to an alteration of DA release within the striatum.

Electronic Resource

1619-7089

Technetium 99m hexamethylpropylene amine oxime ((99m)Tc-HMPAO) ; Single photon emission computed tomography (SPET) ; Alzheimer's disease ; Pick's disease ; Parkinson's disease ; Progressive supranuclear palsy ; Dementia

Springer Online Journal Archives 1860-2000

Medicine

Abstract Regional cerebral perfusion was evaluated by single photon emission computed tomography (SPET) using technetium 99m hexamethylpropylene amine oxime (99mTc-HMPAO) as a tracer, in 13 control subjects and 44 age-matched patients suffering from dementia of the Alzheimer's type (DAT, n=19), presumed Pick's disease (n=5), idiopathic Parkinson's disease with dementia (DPD, n=15) and progressive supranuclear palsy (PSP, n=5). HMPAO uptake was measured in the superior frontal, inferior frontal, parietal, temporal and occipital cortices, and the perfusion values were expressed as cortical/cerebellar activity ratios. As compared with controls, tracer uptake ratios in the DAT group were significantly reduced over all cortical regions, with the largest defects in the parieto-temporal and superior frontal cortices. A marked hypoperfusion affecting the superior and inferior frontal cortices was found in Pick's disease, whereas a mild but significant hypoperfusion was observed only in the superior frontal cortex of patients with PSP. In the DPD group, HMPAO uptake was significantly reduced in the parietal, temporal and occipital cortices, but not in the frontal cortex. These results show that DAT and DPD share an opposite anteroposterior HMPAO uptake defect as compared with the Pick's and PSP groups.

Electronic Resource