Papers by Denis Guilloteau
Previous investigations have shown that the lipid composition of cerebral membranes and dopaminer... more Previous investigations have shown that the lipid composition of cerebral membranes and dopaminergic neu- rotransmission are changed under chronic � -linolenic acid diet deficiency in the rat. This study investigated whether these changes could be reversed and if the stage of brain maturation might play a role in the recovery process. The effects of reversion on the fatty acid (FA)
The main objective of the present multicenter study was to evaluate -Iodolisuride (-ILIS) as a ra... more The main objective of the present multicenter study was to evaluate -Iodolisuride (-ILIS) as a radioligand for dopamine receptors in patients (pts) with extrapyramidal diseases when using g-cameras of different types. 45 pts (28M, 17F) were studied in 2 centers (23+22 pts) and were divided in 2 groups: group I (n=28 age=66.8±3.5 years): idiopathic Parkinson’s disease; group II (n=17, age=57.5±7.1 years): other extrapyramidal syndromes. -ILIS (1.7 to 2.8 MBq/kg) was injected after informed consent. Single photon emission computed tomography (SPECT) studies were performed with a single head -camera (-camera A, GE 400AC*, 24 studies 1 hr p.i.), a dual head -camera (-camera B, Helix Elscint*, 15 studies 1hr to 2.5hr p.i.), a triple head -camera (-camera C, Neurocam GE*, 12 studies 45min to 2hr p.i.) and a brain dedicated annular detector (-camera -camera D, Ceraspect DSI*, 17 studies 1 to 3.5hr p.i.). Patients showed no undesirable reactions. All SPECT images obtained with different -ca...
The Journal of Lipid Research
The influence of aging (2, 6, 12, and 24 months) on hippocampal lipid composition and neurochemic... more The influence of aging (2, 6, 12, and 24 months) on hippocampal lipid composition and neurochemical markers (endogenous noradrenaline, serotonin levels, monoamine oxidase (MOA) activities) was studied in rats fed a control or an n-3 polyunsaturated fatty acid (PUFA)-deficient diet. The n-3 PUFA deficiency reduced the 22:6 (n-3) level, compensated by the increase in 22:5 (n-6). However, the difference in 22:6 (n-3) content between control and deficient rats was less between 2 and 12 months and then became stable. There was an overall age-induced decrease in the major phospholipid classes phosphatidylethanolamine (PE), and phosphatidylcholine (PC) whereas the minor classes, phosphatidylinositol (PI), phosphatidylserine (PS), and sphingomyelin (SM), were greatly increased, regardless of diet. The n-3 PUFA deficiency induced a reduction in the PS level, concomitant with a higher level in MAO-B activity as compared to control rats at the age of 24 months. The age-related evolution of the...
Journal of Nuclear Medicine
Ugand IC 50 (nM)
Journal of Nutrition
We studied the effects of a fish oil enriched diet on fatty acid composition of cerebral membrane... more We studied the effects of a fish oil enriched diet on fatty acid composition of cerebral membranes and on several neurochemical and behavioral variables of monoaminergic function in rats. The frontal cortex, striatum, hippocampus and cerebellum were studied in rats fed fish oil (FPO, 50% salmon oil + 50% palm oil), which provided an (n-6)/(n-3) polyunsaturated fatty acid (PUFA) ratio of 0.14 versus 6. 19 in controls fed a diet containing a mixture of African peanut oil and rapeseed oil. In the FPO group compared to the control group, the major modifications in fatty acid composition of cerebral membranes included the following: higher levels in 22:6(n-3), lower levels in 20:4(n-6) and a significantly greater proportion of phosphatidylserine. Dopamine levels were 40% greater in the frontal cortex of rats fed FPO than from those fed the control diet. In this cerebral region there was also a reduction in monoamine oxidase B (MAO-B) activity and greater binding to dopamine D2 receptors....
The Journal of Lipid Research
Previous investigations have shown that the lipid composition of cerebral membranes and dopaminer... more Previous investigations have shown that the lipid composition of cerebral membranes and dopaminergic neurotransmission are changed under chronic alpha-linolenic acid diet deficiency in the rat. This study investigated whether these changes could be reversed and if the stage of brain maturation might play a role in the recovery process. The effects of reversion on the fatty acid (FA) composition and dopaminergic neurotransmission were studied in brain regions known to be affected by such deficiency (i.e., the prefrontal cortex and nucleus accumbens) in 2-month-old animals. Dopamine release under pharmacological stimulation was studied using a dual-probe microdialysis method. Vesicular monoamine transporters were studied using quantitative autoradiography. The reversal diet, with adequate levels of n-6 and n-3 polyunsaturated fatty acids (PUFAs), was given to deficient rats at different stages of development (0, 7, 14, or 21 days of age). The results showed that when given during the ...
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Annales de biologie clinique
Steroid hormone measurement, first developed with radioimmunoassay, is now becoming easier with t... more Steroid hormone measurement, first developed with radioimmunoassay, is now becoming easier with the use of automated platforms of immunoassay. However, some hormones remain uneasily detectable because of their low blood concentration, their structural homology or the presence of interferences. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) can be considered as an alternative to immunoassays. This approach allows the simultaneous determination of several parameters thanks to its selectivity led by the detector mass spectrometer and the separate dimension of chromatography liquid. In addition, recourse to UHPLC (ultra high performance liquid chromatography) allows improving selectivity and sensitivity while limiting the samples volumes. The "ready-to-use" kits are now available and added to the "homemade" techniques developed by laboratories, thus giving opportunity for measurement of a wide steroid panel with only one sample. Finally, mass spectrometry ...
The accumulation of [3H]spiperone and [3H]dopamine was measured in striatum and pituitary gland s... more The accumulation of [3H]spiperone and [3H]dopamine was measured in striatum and pituitary gland slices of rat. Contrary to [3H]dopamine, [3H]spiperone storage was similar in striatum and pituitary gland. In addition, [3H]spiperone accumulation was not diminished by reserpine and tetrabenazine. These data show that spiperone is not subject to the granular uptake/storage mechanism and suggest that spiperone and its derivatives are specific ligands for dopamine receptors only.
The uptake and release of mIBG, a tracer of the monoamine uptake and storage function, were studi... more The uptake and release of mIBG, a tracer of the monoamine uptake and storage function, were studied on superfused rat cerebral cortex sections. mIBG was taken up and released by a mechanism comparable to that of norepinephrine (NE), but this storage appeared to be less specific for mIBG than for NE. This implies that when mIBG is used as a scintigraphic tracer of monoaminergic synaptic vesicles, imaging should be delayed long enough to ensure release of the molecule from its nonspecific binding sites,
To detect quantitative modification of dopamine D-l receptors in vivo, we used [1251]-TISCH in an... more To detect quantitative modification of dopamine D-l receptors in vivo, we used [1251]-TISCH in an animal modelin which the striatum was unilaterally lesioned with quinolinic acid. ['251]-TISCH was injected into rats 5 days after the lesion, and the changes in receptor density obtained in viva were compared to in vitro quantification of dopamine D-l receptors by binding with either [1251]-TISCH or [3H]-SCH 23390 as a reference ligand. In viva and in vitro, we obtained the same decrease (-70%) in binding of these ligands in the lesioned striatum. Using an injection of [ 99"Tc]-DTPA to lesioned rats, we also showed the disruption of the blood-brain barrier (BBB) in the lesioned area. Thus, the equivalent decrease observed in vitro and in viva with ['251]-TISCH confirmed that this molecule would be a valuable tool for exploration of dopamine D-l receptors by SPECT imaging. Moreover, the fact that the breakdown of the BBB did not interfere with the receptor binding obtained in vivo may be important for future investigations in pathologies with BBB disruption, such as ischemia. NUCL MED BIOL 23;1:75-79, 1996.
Journal of Alzheimer's disease: JAD
Posterior cortical atrophy (PCA) is characterized by progressive higher-order visuo-perceptual dy... more Posterior cortical atrophy (PCA) is characterized by progressive higher-order visuo-perceptual dysfunction and praxis declines. This syndrome is related to several underlying diseases, including Alzheimer's disease (AD), sometimes involving an amyloidogenic process. The aims of the study were to 1) define cerebrospinal fluid (CSF) biomarker profiles in PCA patients compared to AD patients and 2) explore the amyloidogenic process through the Aβ42/Aβ40 ratio in PCA patients to elucidate the underlying disease in vivo. CSF biomarker analysis (t-tau, p-tau, Aβ42, and Aβ42/Aβ40 ratio) and neuropsychological examination were performed in 22 PCA patients and compared with those of age-matched AD patients. Associated clinical neurological signs were investigated (e.g., extrapyramidal motor signs, myoclonus). CSF biomarker profiles did not differ significantly between the PCA and AD groups; 82% of patients with PCA fulfilled the biological criteria for typical AD with abnormal levels of ...
European Journal of Medicinal Chemistry, 2014
Design of a7 nicotinic acetylcholine receptor ligands in quinuclidine, tropane and quinazoline se... more Design of a7 nicotinic acetylcholine receptor ligands in quinuclidine, tropane and quinazoline series. Chemistry, molecular modeling, radiochemistry, in vitro and in rats evaluations of a [ 18 F] quinuclidine derivative a b s t r a c t
International Journal of Developmental Neuroscience, 2008
This article has been withdrawn at the request of the author(s) and/or editor. The Publisher apol... more This article has been withdrawn at the request of the author(s) and/or editor. The Publisher apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found at http://www.elsevier.com/locate/withdrawalpolicy.
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Papers by Denis Guilloteau