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Published on: September 20, 2011
Neuronal platelet-activating factor receptor signal transduction involves a pertussis toxin-sensitive G-protein
G D Clark1, C F Zorumski, R S McNeil
1The Cain Foundation Laboratories, Baylor College of Medicine, Houston, TX, USA. gclark@bcm.tmc.edu
Neurochemical Research
|July 25, 2000
Summary
Platelet-activating factor (PAF) triggers neuronal growth cone collapse and enhances synaptic release via pertussis toxin-sensitive G-proteins. This study identifies these G-proteins as key mediators of PAF receptor signaling in primary neurons.
Area of Science:
- Neuroscience
- Cellular Signaling
- Molecular Biology
Background:
- Platelet-activating factor (PAF) receptors in non-neuronal systems are typically linked to pertussis toxin-sensitive G-proteins.
- These G-proteins mediate cellular responses, including calcium mobilization via inositol triphosphate.
Purpose of the Study:
- To investigate the role of pertussis toxin-sensitive G-proteins in mediating PAF receptor effects in primary neurons.
- To determine if these G-proteins are involved in growth cone collapse and synaptic enhancement.
Main Methods:
- Primary neuronal cultures were utilized.
- Infrared differential interference contrast microscopy and patch-clamp recording techniques were employed.
- The effects of pertussis toxin and its inactive B oligomer on PAF receptor-mediated responses were assessed.
Main Results:
- Pertussis toxin significantly blocked PAF-induced growth cone collapse.
- Pertussis toxin also inhibited the enhanced synaptic release of excitatory transmitter.
- The inactive B oligomer of pertussis toxin did not produce these effects, indicating specificity.
- These findings suggest that Go, Gq, or Gi are likely G-protein transducers for PAF receptors in neurons.
Conclusions:
- PAF directly engages neuronal receptors linked to pertussis toxin-sensitive G-proteins.
- These signaling pathways regulate crucial neuronal development and function, including neurite outgrowth and synaptic transmission.
- The identified G-proteins are critical for mediating PAF's effects on growth cone collapse and synaptic enhancement.
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