AI Article Synopsis
- A new cardiac imaging agent, [(18)F]4F-MHPG, was developed to assess sympathetic nerve activity in the heart.
- Initial studies on rats showed that the uptake and retention of this agent in nerve cells were promising, similar to an earlier carbon-11 version.
- PET imaging in nonhuman primates demonstrated excellent image quality and suggest that [(18)F]4F-MHPG could improve the quantification of cardiac sympathetic nerve density compared to current methods.
Article Abstract
A new cardiac sympathetic nerve imaging agent, [(18)F]4-fluoro-m-hydroxyphenethylguanidine ([(18)F]4F-MHPG), was synthesized and evaluated. The radiosynthetic intermediate [(18)F]4-fluoro-m-tyramine ([(18)F]4F-MTA) was prepared and then sequentially reacted with cyanogen bromide and NH4Br/NH4OH to afford [(18)F]4F-MHPG. Initial bioevaluations of [(18)F]4F-MHPG (biodistribution studies in rats and kinetic studies in the isolated rat heart) were similar to results previously reported for the carbon-11 labeled analog [(11)C]4F-MHPG. The neuronal uptake rate of [(18)F]4F-MHPG into the isolated rat heart was 0.68ml/min/g wet and its retention time in sympathetic neurons was very long (T1/2 >13h). A PET imaging study in a nonhuman primate with [(18)F]4F-MHPG provided high quality images of the heart, with heart-to-blood ratios at 80-90min after injection of 5-to-1. These initial kinetic and imaging studies of [(18)F]4F-MHPG suggest that this radiotracer may allow for more accurate quantification of regional cardiac sympathetic nerve density than is currently possible with existing neuronal imaging agents.
Download full-text PDF |
Source |
|---|---|
| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3594138 | PMC |
| http://dx.doi.org/10.1016/j.bmcl.2013.01.106 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Purpose: The aim of the current study was to evaluate changes in choroidal circulation hemodynamics after periocular skin warming at 40°C using laser speckle flowgraphy (LSFG).
Methods: Twenty-four right eyes of 24 healthy participants were included. Changes in choroidal circulation hemodynamics were determined using LSFG to evaluate the mean blur rate (MBR) of the macula, which represents choroidal blood flow velocity.
Comparing autonomic nervous system function in patients with functional somatic syndromes, stress-related syndromes and healthy controls.
J Psychosom Res
December 2024
REVAL - Rehabilitation Research Center, Faculty of Rehabilitation Sciences, Hasselt University, Diepenbeek, Belgium; Health Psychology, Faculty of Psychology and Educational Sciences, KU Leuven, Leuven, Belgium. Electronic address:
Background: The goal of this study was to examine autonomic nervous system function by measuring heart rate (HR), heart rate variability (HRV), skin conductance levels (SCL), and peripheral skin temperature (ST) in response to and during recovery from psychosocial stressors in patients with functional somatic syndromes (FSS; fibromyalgia and/or chronic fatigue syndrome), stress-related syndromes (SRS; overstrain or burn-out), and healthy controls (HC).
Methods: Patients with FSS (n = 26), patients with SRS (n = 59), and HC (n = 30) went through a standardized psychosocial stress test consisting of a resting phase (120 s), the STROOP color word task (120 s), a mental arithmetic task (120 s) and a stress talk (120 s), each followed by a 120 s recovery period. HR, HRV, SCL, and ST were monitored continuously.
Emotional Stress in Cardiac and Vascular Diseases.
Curr Vasc Pharmacol
January 2025
Department of Cardiology, Ippokrateio University Hospital, Athens, Greece.
Introduction/objective: Emotional, mental, or psychological distress, defined as increased symptoms of depression, anxiety, and/or stress, is common in patients with chronic diseases, such as cardiovascular (CV) disease (CVD).
Methods: Literature was reviewed regarding data from studies and meta-analyses examining the impact of emotional stress on the occurrence and outcome of several CVDs (coronary disease, heart failure, hypertension, arrhythmias, stroke). These influences' pathophysiology and clinical spectrum are detailed, tabulated, and pictorially illustrated.
Sympathetic nervous system inhibition enhances cardiac metabolism and improves hemodynamics and glucose-insulin dynamics in obese and lean rat models.
Sci Rep
January 2025
Department of Pharmacology, "Grigore T. Popa" University of Medicine and Pharmacy, 16 University St., Iași, Romania.
This study aimed to investigate the effects of chronic sympathoinhibition on glucose uptake by the myocardium and by the skeletal muscle in an animal model of obesity associated with leptin signaling deficiency. 6 obese Zucker rats (OZR) and 6 control Lean Zucker rats (LZR) were studied during basal conditions, chronic clonidine administration (30 days, 300 µg/kg), and washout recovery period. Glucose uptake in the myocardium and in the skeletal muscle was measured using positron emission tomography (PET) and 2-[18F] fluoro-2-deoxy-D-glucose ([18F]FDG).
View Article and Find Full Text PDFCardiac Presynaptic Sympathetic Nervous Function Evaluated by Cardiac PET in Patients with Chronotropic Incompetence Without Heart Failure.
J Nucl Med
January 2025
Department of Cardiology, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan.
Chronotropic incompetence (CTI), the inability of the heart to increase its rate with increased activity, leads to exercise intolerance and predicts overall mortality. We previously reported that cardiac β-adrenergic receptor downregulation occurs in patients with CTI without heart failure (HF), indicating postsynaptic sympathetic nervous dysfunction. However, cardiac presynaptic sympathetic nervous system function in CTI is not fully understood.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!