Dataset Information

Test-Retest Repeatability of [18F]MC225-PET in Rodents: A Tracer for Imaging of P-gp Function.

ABSTRACT: In longitudinal PET studies, animals are repeatedly anesthetized which may affect the repeatability of PET measurements. The aim of this study was to assess the effect of anesthesia on the P-gp function as well as the reproducibility of [18F]MC225 PET scans. Thus, dynamic PET scans with blood sampling were conducted in 13 Wistar rats. Seven animals were exposed to isoflurane anesthesia 1 week before the PET scan ("Anesthesia-exposed" PET). A second group of six animals was used to evaluate the reproducibility of measurements of P-gp function at the blood-brain barrier (BBB) with [18F]MC225. In this group, two PET scans were made with a 1 week interval ("Test" and "Retest" PET). Pharmacokinetic parameters were calculated using compartmental models and metabolite-corrected plasma as an input function. "Anesthesia-exposed" animals showed a 28% decrease in whole-brain volume of distribution (VT) (p < 0.001) compared to "Test", where the animals were not previously anesthetized. The VT at "Retest" also decreased (19%) compared to "Test" (p < 0.001). The k2 values in whole-brain were significantly increased by 18% in "Anesthesia-exposed" (p = 0.005) and by 15% in "Retest" (p = 0.008) compared to "Test". However, no significant differences were found in the influx rate constant K1, which is considered as the best parameter to measure the P-gp function. Moreover, Western Blot analysis did not find significant differences in the P-gp expression of animals not pre-exposed to anesthesia ("Test") or pre-exposed animals ("Retest"). To conclude, anesthesia may affect the brain distribution of [18F]MC225 but it does not affect the P-gp expression or function.

SUBMITTER: Garcia-Varela L

PROVIDER: S-EPMC7034080 | biostudies-literature | 2020 Feb

REPOSITORIES: biostudies-literature

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Test-Retest Repeatability of [<sup>18</sup>F]MC225-PET in Rodents: A Tracer for Imaging of P-gp Function.

García-Varela Lara L Vállez García David D Rodríguez-Pérez Manuel M van Waarde Aren A Sijbesma Jürgen W A JWA Schildt Anna A Kwizera Chantal C Aguiar Pablo P Sobrino Tomás T Dierckx Rudi A J O RAJO Elsinga Philip H PH Luurtsema Gert G

ACS chemical neuroscience 20200203 4

In longitudinal PET studies, animals are repeatedly anesthetized which may affect the repeatability of PET measurements. The aim of this study was to assess the effect of anesthesia on the P-gp function as well as the reproducibility of [<sup>18</sup>F]MC225 PET scans. Thus, dynamic PET scans with blood sampling were conducted in 13 Wistar rats. Seven animals were exposed to isoflurane anesthesia 1 week before the PET scan ("Anesthesia-exposed" PET). A second group of six animals was used to eva ...[more]

PMID: 31961646

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Dataset Information

Test-Retest Repeatability of [18F]MC225-PET in Rodents: A Tracer for Imaging of P-gp Function.

Publications

Test-Retest Repeatability of [<sup>18</sup>F]MC225-PET in Rodents: A Tracer for Imaging of P-gp Function.

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