Abstract
In vitro antigen challenge has multiple effects on the excitability of guinea pig bronchial parasympathetic ganglion neurons, including depolarization, causing phasic neurons to fire with a repetitive action potential pattern and potentiating synaptic transmission. In the present study, guinea pigs were passively sensitized to the antigen ovalbumin. After sensitization, the bronchi were prepared for in vitro electrophysiological intracellular recording of parasympathetic ganglia neurons to investigate the contribution of cyclooxygenase activation and prostanoids on parasympathetic nerve activity. Cyclooxygenase inhibition with either indomethacin or piroxicam before in vitro antigen challenge blocked the change in accommodation. These cyclooxygenase inhibitors also blocked the release of prostaglandin D2 (PGD2) from bronchial tissue during antigen challenge. We also determined that PGE2 and PGD2 decreased the duration of the action potential after hyperpolarization, whereas PGF2α potentiated synaptic transmission. Thus prostaglandins released during antigen challenge have multiple effects on the excitability of guinea pig bronchial parasympathetic ganglia neurons, which may consequently affect the output from these neurons and thereby alter parasympathetic tone in the lower airways.
Original language | English (US) |
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Pages (from-to) | L581-L587 |
Journal | American Journal of Physiology - Lung Cellular and Molecular Physiology |
Volume | 284 |
Issue number | 4 28-4 |
DOIs | |
State | Published - Apr 1 2003 |
Keywords
- Asthma
- Bronchoconstriction
- Ganglia
- Guinea pig
- Synaptic transmission
ASJC Scopus subject areas
- Physiology
- Pulmonary and Respiratory Medicine
- Physiology (medical)
- Cell Biology