Several inward rectifier K+ (Kir) channels are inhibited by hypercapnic acidosis and may be involved in CO2 central chemoreception. Among them are Kir1.1, Kir2.3, and Kir4.1. The Kir4.1 is expressed predominantly in the brainstem. Although its CO2 sensitivity is low, coexpression of Kir4.1 with Kir5.1 in Xenopus oocytes greatly enhances the CO2/pH sensitivities of the heteromeric channels. If these Kir channels play a part in the central CO2 chemosensitivity, they should be expressed in neurons of brainstem cardio-respiratory nuclei. To test this hypothesis, we performed in-situ hybridization experiments in which the expression of Kir1.1, Kir2.3, Kir4.1 and Kir5.1, and coexpression of Kir4.1 and Kir5.1 were studied in brainstem neurons using non-radioactive riboprobes. We found that mRNAs of these Kir channels were present in several brainstem nuclei, especially those involved in cardio-respiratory controls. Strong labeling was observed in the locus coeruleus, ventralateral medulla, parabrachial-Kölliker-Fuse nuclei, solitary tract nucleus, and area postrema. Strong expression was also seen in several cranial motor nuclei, including the nucleus of ambiguus, hypoglossal nucleus, facial nucleus and dorsal vagus motor nucleus. In general, the expression of Kir5.1 and Kir4.1 was much more prominent than that of Kir1.1 and Kir2.3 in all the nuclei. Evidence for the coexpression of Kir4.1 and Kir5.1 was found in a good number of neurons in these nuclei. The expression and coexpression of these CO2/pH-sensitive Kir channels suggest that they are likely to contribute to CO2 chemosensitivity of the brainstem neurons.
The Journal of Membrane Biology – Springer Journals
Published: Jan 1, 2004
It’s your single place to instantly
discover and read the research
that matters to you.
Enjoy affordable access to
over 18 million articles from more than
15,000 peer-reviewed journals.
All for just $49/month
Query the DeepDyve database, plus search all of PubMed and Google Scholar seamlessly
Save any article or search result from DeepDyve, PubMed, and Google Scholar... all in one place.
Get unlimited, online access to over 18 million full-text articles from more than 15,000 scientific journals.
Read from thousands of the leading scholarly journals from SpringerNature, Elsevier, Wiley-Blackwell, Oxford University Press and more.
All the latest content is available, no embargo periods.
“Hi guys, I cannot tell you how much I love this resource. Incredible. I really believe you've hit the nail on the head with this site in regards to solving the research-purchase issue.”Daniel C.
“Whoa! It’s like Spotify but for academic articles.”@Phil_Robichaud
“I must say, @deepdyve is a fabulous solution to the independent researcher's problem of #access to #information.”@deepthiw
“My last article couldn't be possible without the platform @deepdyve that makes journal papers cheaper.”@JoseServera