OtherBASIC SCIENCE INVESTIGATIONS

In Vivo PET Imaging of Cardiac Presynaptic Sympathoneuronal Mechanisms in the Rat

Dnyanesh N. Tipre, James J. Fox, Daniel P. Holt, Gilbert Green, Jianhua Yu, Martin Pomper, Robert F. Dannals and Frank M. Bengel
Journal of Nuclear Medicine July 2008, 49 (7) 1189-1195; DOI: https://doi.org/10.2967/jnumed.107.050252

Article Figures & Data

Figures

  • FIGURE 1. 
    FIGURE 1. 

    Schematic display of neuronal pathways tracked by 3 different sympathoneuronal PET tracers.

  • FIGURE 2. 
    FIGURE 2. 

    Representative static coronal PET images and reangulated, smoothed cardiac images of rats, acquired between 50 and 60 min after intravenous injection of HED, PHEN, or EPI. Shown on right are midventricular short-axis (SA), vertical long-axis (VLA), and horizontal long-axis slices (HLA). Liver is visualized inferior to left ventricle.

  • FIGURE 3. 
    FIGURE 3. 

    Myocardial time–activity curves for LV chamber (□), LV lateral wall (▵), LV septum (▿), LV apex (⋄), and liver (*) in rats after intravenous injection of HED, without pharmacologic intervention (A), with intraperitoneal administration of 2 mg of DMI solution per kilogram 15 min after tracer injection (DMI chase) (B), and after intraperitoneal administration of 2 mg of DMI solution per kilogram 15 min before tracer injection (DMI block) (C). A and B show data averaged from 4 rats, and C shows observation from 1 rat (LV septum and LV apex were included in FOV but not detectable in C; kinetics in anterior wall were also analyzed but did not differ from other myocardial regions and are therefore not shown).

  • FIGURE 4. 
    FIGURE 4. 

    Myocardial time–activity curves of radioactivity in LV chamber (□), LV lateral wall (▵), LV septum (▿), LV apex (⋄), and liver (*) in rats after intravenous injection of PHEN, without pharmacologic intervention (A), with intraperitoneal administration of 2 mg of DMI solution per kilogram 15 min after tracer injection (DMI chase) (B), and after intraperitoneal administration of 2 mg of DMI solution per kilogram 15 min before tracer injection (DMI block) (C). A and B show data averaged from 4 rats, and C shows observation from 1 rat (LV septum and LV apex were included in FOV but not detectable in C; kinetics in anterior wall were also analyzed but did not differ from other myocardial regions and are therefore not shown).

  • FIGURE 5. 
    FIGURE 5. 

    Myocardial time–activity curves of radioactivity in LV chamber (□), LV lateral wall (▵), LV septum (▿), LV apex (⋄), and liver (*) in rats after intravenous injection of EPI, without pharmacologic intervention (A), with lower specific radioactivity without pharmacologic intervention (B), after intraperitoneal administration of 2 mg of DMI solution per kilogram 15 min after tracer injection (DMI chase) (C), and after intraperitoneal administration of 2 mg of DMI solution pre kilogram 15 min before tracer injection (DMI block) (D). A, B, and C show data averaged from 4 rats, and D shows observation from 1 rat (LV septum and LV apex were included in FOV but not detectable in D; kinetics in anterior wall were also analyzed but did not differ from other myocardial regions and are therefore not shown).

Tables

  • TABLE 1

    Non–Metabolite-Corrected Myocardial Retention Index and Washout Rate of Radiotracers With and Without Treatment With DMI

    Retention index (%/min at 40 min)Washout rate (%/min between 10 and 60 min)
    RadiotracerWithout intervention (n = 4)DMI chase (n = 4)DMI pretreatment (n = 1)Without intervention (n = 4)DMI chase (n = 4)DMI pretreatment (n = 1)
    HED7.38 ± 0.823.28 ± 0.60*0.21 ± 0.35†0.13 ± 0.231.86 ± 0.57*‡
    PHEN3.43 ± 0.452.95 ± 0.51*0.24 ± 0.25†1.13 ± 0.351.51 ± 0.16‡
    EPI4.24 ± 0.594.02 ± 0.990.22 ± 0.30†0.50 ± 0.240.61 ± 0.28‡
    EPI (low specific radioactivity)3.87 ± 0.81——0.69 ± 0.17——

    • ↵* P < 0.05 vs. animals without intervention.

    • ↵† Single-case observation precludes statistical testing, but values are markedly reduced.

    • ↵‡ Complete washout of radiotracer from myocardium in first 10 min in DMI pretreated rats.

    • Values are average ± SD from septal, lateral, inferior, anterior, and apex regions of left ventricle.

Back to top

In this issue

Print
Download PDF
Article Alerts
Email Article
Citation Tools
Bookmark this article

Jump to section