Binding kinetics of 11C-N-methyl piperidyl benzilate (11C-NMPB) in a rhesus monkey brain using the cerebellum as a reference region.

نویسندگان

  • Takashi Itoh
  • Masayasu Tanaka
  • Kaoru Kobayashi
  • Kazutoshi Suzuki
  • Osamu Inoue
چکیده

The binding kinetics of 11C-N-methyl piperidyl benzilate (11C-NMPB) in rhesus monkey brain were studied using animal positron emission tomography (PET) (SHR2000). This study is intended to assess the validity of the method using the cerebellum as a reference region, and to evaluate the effects of anesthesia on 11C-NMPB binding. Two monkeys, anesthetized with ketamine, received intravenous 11C-NMPB alone (370-760 MBq, < 1 microg/kg) or mixed with varying doses of nonradioactive NMPB (3 microg/kg, 10 microg/kg, 30 microg/kg) and were subjected to PET scans for 60 minutes. Regions of interest (ROI) were drawn on reconstructed PET images and a time-activity curve was obtained for each region. 11C-NMPB accumulated densely in the striatum and cerebral cortex with time. In contrast, the tracer accumulation significantly decreased with increased doses of nonradioactive NMPB. In the cerebellum, on the other hand, the accumulation of 11C-NMPB remained low and the tracer was slowly eliminated from the brain following the injection. 11C-NMPB binding in the cerebellum was barely affected by the increased dose of nonradioactive NMPB. We thus concluded that the specific 11C-NMPB binding was negligible in the cerebellum, and performed simplified evaluation of 11C-NMPB binding in each brain region by a graphical method using the cerebellum as a reference region. PET was conducted 26 times, in total both in ketamine-anesthetized and awake monkeys (n = 3 each). Measurements of 11C-NMPB binding showed good run-to-run reproducibility within individual animals. When 11C-NMPB binding was compared between ketamine-treated and awake animals, a significant increase in 11C-NMPB binding was observed in the striatum but not in other brain regions of ketamine-treated animals.

برای دانلود رایگان متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Sex-related differences in the muscarinic acetylcholinergic receptor in the healthy human brain--a positron emission tomography study.

We evaluated the sex-related differences in the decline of the cerebral muscarinic acetylcholinergic receptor (mACh-R) due to aging by using 11C-N-methyl-4-piperidyl benzilate (11C-NMPB) and positron emission tomography (PET). The subjects consisted of 37 (20 males and 17 females) healthy volunteers. The 11C-NMPB uptake was evaluated by the ratio method (regional 11C-NMPB uptake/Cerebellar 11C-...

متن کامل

Assessment of muscarinic receptor concentrations in aging and Alzheimer disease with [11C]NMPB and PET.

Cerebral cholinergic deficits have been described in Alzheimer disease (AD) and as a result of normal aging. At the present time, there are very limited options for the quantification of cholinergic receptors with in vivo imaging techniques such as PET. In the present study, we examined the feasibility of utilizing [11C]N-methyl-4-piperidyl benzilate (NMPB), a nonselective muscarinic receptor l...

متن کامل

(R)-N-[11C]methyl-3-pyrrolidyl benzilate, a high-affinity reversible radioligand for PET studies of the muscarinic acetylcholine receptor.

We recently reported the synthesis and binding affinity of ligands for the muscarinic acetylcholine receptor (mAChR) based on both the pyrrolidyl and piperidyl benzilate scaffold. One of these, (R)-3-pyrrolidyl benzilate, was successfully radiolabeled with [(11)C]methyl triflate and the resulting compound, (R)-N-[(11)C]methyl-3-pyrrolidyl benzilate (3-[(11)C]NMPYB), was evaluated as a reversibl...

متن کامل

Whole-Body Distribution of Donepezil as an Acetylcholinesterase Inhibitor after Oral Administration in Normal Human Subjects: A 11C-donepezil PET Study

Objective(s): It is difficult to investigate the whole-body distribution of an orally administered drug by means of positron emission tomography (PET), owing to the short physical half-life of radionuclides, especially when 11C-labeled compounds are tested. Therefore, we aimed to examine the whole-body distribution of donepezil (DNP) as an acetylcholinesterase inhibitor by means of 11C-DNP PET ...

متن کامل

Fenfluramine Reduces [11C]Cimbi-36 Binding to the 5-HT2A Receptor in the Nonhuman Primate Brain

Background [11C]Cimbi-36 is a serotonin 2A receptor agonist positron emission tomography radioligand that has recently been examined in humans. The binding of agonist radioligand is expected to be more sensitive to endogenous neurotransmitter concentrations than antagonist radioligands. In the current study, we compared the effect of serotonin releaser fenfluramine on the binding of [11C]Cimbi-...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

عنوان ژورنال:
  • Annals of nuclear medicine

دوره 19 6  شماره 

صفحات  -

تاریخ انتشار 2005