The Braking K V 1/D-type Potassium Channels Regulate the Excitability of Bronchopulmonary Vagal Afferent Nerves

• Published in: The FASEB journal 2022-05, Vol.36 Suppl 1 (S1)
• Main Authors: Sun, Hui, Patil, Mayur J, Ru, Fei, Meeker, Sonya, Undem, Bradley J
• Format: Article
• Language: English
• ISSN: 0892-6638; 1530-6860
• DOI: 10.1096/fasebj.2022.36.S1.R5159

The proper function of airway vagal afferent nerves is essential for the dynamic regulation of breathing and initiation of adequate airway defensive reflexes. A better understanding of the mechanisms controlling their activation bears physiological and pathological significance. The voltage-gated potassium (K ) channels exert powerful controls on the neuronal excitability. Yet their expression and functions in the bronchopulmonary vagal afferent neurons remain largely unexplored. In this study we characterized the expression profile and inhibitory function of α-dendrotoxin (α-DTX)-sensitive D-type K channels composed of members of K 1subfamily of α-subunits in mouse bronchopulmonary nodose neurons using a combination of single-neurons RT-PCR, patch clamp recording, ex-vivo extracellular recording and two-photon microscopic Ca imaging techniques. The results showed that the vast majority of retrogradely labeled lung-specific nodose neurons expressed Kcna1, 2 and 6 coding for the α-DTX-sensitive K 1.1, 1.2 and 1.6 α-subunits, respectively. The D-type K current (I ), defined as the α-DTX-sensitive K current, was recorded in 14/15 bronchopulmonary nodose neurons. It started to be activated at -65.7±4.3 mV with 50% channel activation at -24 ± 14 mV. I opened rapidly in response to depolarization (activation time constants