Impaired water reabsorption in mice deficient in the type VI adenylyl cyclase (AC6)

Institute of Life Sciences, National Defense Medical Center, Taipei, Taiwan.
FEBS letters (Impact Factor: 3.17). 07/2010; 584(13):2883-90. DOI: 10.1016/j.febslet.2010.05.004
Source: PubMed


Adenylyl cyclase (AC) type VI (AC6) is a calcium-inhibitable enzyme which produces cAMP upon stimulation. Herein, we characterized the specific role of AC6 in the kidneys using two AC6-knockout mouse lines. Immunohistochemical staining revealed that AC6 exists in the tubular parts of the nephron and collecting duct. Activities of AC evoked by forskolin or a selective agonist of the V2 vasopressin receptor were lower in the kidneys of AC6-null mice compared to those of wildtype mice. Results of a metabolic cage assay and dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) showed for the first time that AC6 plays a critical role in regulating water homeostasis.

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Available from: Yijuang Chern, Apr 28, 2014
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    • "In addition, adult AC6-null mice were more sensitive to experimental handling than WT mice. Although AC6-null mice appeared anatomically normal under basal conditions (Chien et al., 2010), more than 50% of AC6-null mice developed an enlarged colon (Fig. S3) and constipation after being tested using a panel of noninvasive assays such as electrocardiography and echocardiography. No effect of these noninvasive tests on WT mice was observed (Fig. S3). "
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