Publications by authors named "R Besselievre"

The MDR P-glycoprotein has been described as a major factor of multidrug resistance. This transmembrane glycoprotein acts like an energy dependent efflux pump which possesses a broad specificity. It seems to be acting as a pump requiring drug fixation prior to extrusion.

View Article and Find Full Text PDF

beta-Carbolines are competitive ligands of central type benzodiazepine receptors and have been reported to display either agonist, inverse agonist, or antagonist activities in vivo. We studied the in vivo inhibition of [3H]Ro 15-1788 binding in mice by various beta-carbolines of different pharmacological profiles and found that they were all more potent in the cerebellum than in the cortex and hippocampus; their ID50 values (dose inhibiting 50% of the specific binding of [3H]Ro 15-1788) were 3 to 7 times lower in the cerebellum than in the hippocampus. The ID50 of the triazolopyridazine CL 218,872 was 2.

View Article and Find Full Text PDF
Article Synopsis
  • - A new tritiated version of a 5-HT1A photoaffinity probe was created and used to label specific receptor binding sites in rat brain membranes, particularly focusing on the hippocampus.
  • - The labeling process incorporated a 63-kilodalton protein, referred to as PI, which showed a strong connection to the 5-HT1A receptor sites, as its labeling could be blocked by specific 5-HT1A ligands but not by other types of drugs.
  • - The study concluded that the 63-kilodalton protein PI is likely the binding subunit of the 5-HT1A receptor and contains important sulfhydryl groups that play a critical role in its function.
View Article and Find Full Text PDF

Two complementary approaches, covalent labelling and solubilization, have been used to study the biochemical properties of the central 5-HT1A receptor binding site. We have first designed a photoaffinity ligand containing the structure of 8-OH-DPAT, a potent and specific agonist of 5-HT1A sites. Thus, 8-methoxy-2[N-n-propyl,N-3-(2-nitro-4-azido-phenyl)- aminopropyl]aminotetralin or 8-methoxy-3'-NAP-amino-PAT, was found to displace, in the dark, [3H]8-OH-DPAT from 5-HT1A sites in rat hippocampal membranes with an IC50 of 6.

View Article and Find Full Text PDF

The synthesis and binding properties to rat brain tissue of the enkephalinase inhibitor [3H] N-[(R,S)-3-hydroxyaminocarbonyl-2-benzyl-1-oxopropyl]-glycine ([3H]HACBO-Gly, 45 Ci/mmole) is reported. [3H]HACBO-Gly binding to membranes from various rat brain tissue is saturable (KD = 0.4 +/- 0.

View Article and Find Full Text PDF