کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
2847220 1167343 2013 11 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Bicarbonate-sensitive soluble and transmembrane adenylyl cyclases in peripheral chemoreceptors
موضوعات مرتبط
علوم زیستی و بیوفناوری بیوشیمی، ژنتیک و زیست شناسی مولکولی فیزیولوژی
پیش نمایش صفحه اول مقاله
Bicarbonate-sensitive soluble and transmembrane adenylyl cyclases in peripheral chemoreceptors
چکیده انگلیسی


• In the carotid body, sAC and tmAC are functional and contribute to cAMP accumulation under normocapnic conditions.
• Isohydric hypercapnia causes no changes on cAMP levels, PKA activity and carotid sinus nerve discharge.
• Carotid body hypercapnic response is not dependent on increases in CO2/HCO3−.

Stimulation of the carotid body (CB) chemoreceptors by hypercapnia triggers a reflex ventilatory response via a cascade of cellular events, which includes generation of cAMP. However, it is not known if molecular CO2/HCO3− and/or H+ mediate this effect and how these molecules contribute to cAMP production. We previously reported that the CB highly expresses HCO3−-sensitive soluble adenylyl cyclase (sAC). In the present study we systematically characterize the role of sAC in the CB, comparing the effect of isohydric hypercapnia (IH) in cAMP generation through activation of sAC or transmembrane-adenylyl cyclase (tmAC).Pharmacological deactivation of sAC and tmAC decreased the CB cAMP content in normocapnia and IH with no differences between these two conditions. Changes from normocapnia to IH did not effect the degree of PKA activation and the carotid sinus nerve discharge frequency.sAC and tmAC are functional in CB but intracellular elevations in CO2/HCO3− in IH conditions on their own are insufficient to further activate these enzymes, suggesting that the hypercapnic response is dependent on secondary acidosis.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Respiratory Physiology & Neurobiology - Volume 188, Issue 2, 15 August 2013, Pages 83–93
نویسندگان
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