The regional distribution in brain, distribution volumes, and pharmacological specificity of the PET 5-HT(2A) receptor radiotracer [(18)F]deuteroaltanserin were evaluated and compared to those of its non-deuterated derivative [(18)F]altanserin. Both radiotracers were administered to baboons by bolus plus constant infusion and PET images were acquired up to 8 h. The time-activity curves for both tracers stabilized between 4 and 6 h. The ratio of total and free parent to metabolites was not significantly different between radiotracers; nevertheless, total cortical R(T) (equilibrium ratio of specific to nondisplaceable brain uptake) was significantly higher (34-78%) for [(18)F]deuteroaltanserin than for [(18)F]altanserin. In contrast, the binding potential (Bmax/K(D)) was similar between radiotracers. [(18)F]Deuteroaltanserin cortical activity was displaced by the 5-HT(2A) receptor antagonist SR 46349B but was not altered by changes in endogenous 5-HT induced by fenfluramine. These findings suggest that [(18)F]deuteroaltanserin is essentially equivalent to [(18)F]altanserin for 5-HT(2A) receptor imaging in the baboon.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/s0969-8051(00)00212-2 | DOI Listing |
Prog Neuropsychopharmacol Biol Psychiatry
January 2025
Louisiana State University, Department of Comparative Biomedical Sciences, Baton Rouge, LA 70803, United States of America. Electronic address:
Renewed interest in the clinical use of psychedelic drugs acknowledges their therapeutic effectiveness. It has also provided a changing frame of reference for older psychedelic drug study data, especially regarding concentrations of N, N-dimethyltryptamine (DMT) reported in rodent brains and recent discoveries in DMT receptor interactions in rat brain neurons and select brain areas. The mode of action of DMT in its newly defined role as a neuroplastogen, its effectiveness in treating neuropsychiatric disorders, and its binding to intracellular sigma-1 and 5HT2a receptors may define these possible roles.
View Article and Find Full Text PDFInt J Mol Sci
December 2024
Neuroscience Research Institute, Gachon University, Incheon 21565, Republic of Korea.
To elucidate the potential roles of presynaptic and postsynaptic serotonergic activity in impulsivity traits, we investigated the relationship between self-reported impulsiveness and serotonin transporter (5-HTT) and 5-HT2A receptors in healthy individuals. In this study, 26 participants completed 3-Tesla magnetic resonance imaging and positron emission tomography with [C]DASB and [C]MDL100907. To quantify 5-HTT and 5-HT2A receptor availability, the binding potential (BP) of [C]DASB and [C]MDL100907 was derived using the simplified reference tissue model with cerebellar gray matter as the reference region.
View Article and Find Full Text PDFJ Med Chem
January 2025
Department of Chemistry, Gwangju Institute of Science and Technology, Gwangju 61005, Republic of Korea.
Colorectal cancer is a prevalent and prominent contributor to global cancer-related fatalities with challenges in drug resistance and metastasis. Recent research highlights the potential relationship between serotonin and cancer. 5-Hydroxytryptamine receptor 2A (HTR2A) mRNA expression in colorectal cancer cells was found to be notably elevated compared to that in normal colon cells.
View Article and Find Full Text PDFArch Razi Inst
June 2024
Medical Plants Research Center, Basic Health Sciences Institute, Shahrekord University of Medical Sciences, Shahrekord, Iran.
In the present study, the mechanisms involved in scopolamine-induced memory impairment have been investigated. The molecular events that take place during memory mostly include mechanisms that are seen in the acquisition phase. Results showed that one of the mechanisms of memory destruction caused by scopolamine, in addition to weakening the cholinergic system, is the indirect effect of scopolamine on other neurotransmitter systems, including the glutamatergic system.
View Article and Find Full Text PDFBrain Res
December 2024
Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen 2100, Denmark. Electronic address:
Psychedelics show promise in treating psychiatric disorders. Therapeutic effects appear to involve activation of the 5-Hydroxytryptamine 2A receptor (5-HTR), a G protein-coupled receptor (GPCR). Several SNPs of the 5-HTR naturally occur, which are associated with differences in receptor function and altered responsiveness to treatments.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!