Intrapleural siRNAs targeting PKCθ block pLTF. A, Representative phrenic neurograms after AIH from rats given three, daily intrapleural injections of nontargeting siRNAs (NTsiRNA, n = 7, top), PKCθ targeting siRNAs (siPKCθ, n = 7, middle), or PKCζ targeting siRNAs (siPKCζ, n = 5, bottom). Horizontal dotted line indicates baseline amplitude. Gray represents increases from baseline. B, Summary data demonstrate significant pLTF at 30 and 60 min after AIH in NTsiRNA and siPKCζ groups, but not with siPKCθ. Rats given intrapleural NTsiRNA (n = 4), siPKCθ (n = 3), or siPKCζ (n = 3) without AIH (time controls, n = 10) did not exhibit significant facilitation at 60 min. *p < 0.05 versus time controls. #p < 0.05 versus siPKCζ or NTsiRNA.