Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2013 Sep;386(9):761-73.
doi: 10.1007/s00210-013-0860-5. Epub 2013 Apr 6.

β2-adrenoceptor agonists can both stimulate and inhibit glucose uptake in mouse soleus muscle through ligand-directed signalling

Affiliations

β2-adrenoceptor agonists can both stimulate and inhibit glucose uptake in mouse soleus muscle through ligand-directed signalling

Robert A Ngala et al. Naunyn Schmiedebergs Arch Pharmacol. 2013 Sep.

Abstract

The β-adrenoceptor agonists BRL37344 and clenbuterol have opposite effects on glucose uptake in mouse soleus muscle, even though the β2-adrenoceptor mediates both effects. Different agonists may direct the soleus muscle β2-adrenoceptor to different signalling mechanisms. Soleus muscles were incubated with 2-deoxy[1-(14)C]-glucose, β-adrenoceptor agonists, other modulators of cyclic AMP, and inhibitors of intracellular signalling. The adenylyl cyclase activator forskolin (1 μM), the phosphodiesterase inhibitor rolipram (10 μM) and BRL37344 (10, but not 100 or 1,000, nM) increased, whereas clenbuterol (100 nM) decreased, glucose uptake. Forskolin increased, whereas clenbuterol decreased, muscle cyclic AMP content. BRL37344 (10 nM) did not increase cyclic AMP. Nevertheless, protein kinase A (PKA) inhibitors prevented the stimulatory effect of BRL37344. Nanomolar but not micromolar concentrations of adrenaline stimulated glucose uptake. After preincubation of muscles with pertussis toxin (100 ng/ml), 100 nM clenbuterol, 0.1-10 μM adrenaline and 100 nM BRL37344 stimulated glucose uptake. Clenbuterol increased the proportion of phosphorylated to total β2-adrenoceptor. Inhibitors of phosphatidylinositol 3-kinase (PI3K) and the stress-activated mitogen-activated protein kinase (MAPK), but not of the classical MAPK pathway, prevented stimulation of glucose uptake by BRL37344. Elevation of the cyclic AMP content of soleus muscle stimulates glucose uptake. Clenbuterol, and high concentrations of adrenaline and BRL37344 direct the β2-adrenoceptor partly to Gαi, possibly mediated by β2-adrenoceptor phosphorylation. The stimulatory effect of 10 nM BRL37344 requires the activity of PKA, PI3K and p38 MAPK, consistent with BRL37344 directing the β2-adrenoceptor to Gαs. Ligand-directed signalling may explain why β2-adrenoceptor agonists have differing effects on glucose uptake in soleus muscle.

PubMed Disclaimer

Similar articles

Cited by

References

    1. Br J Pharmacol. 2006 Feb;147(4):446-54 - PubMed
    1. Clin Exp Pharmacol Physiol. 2008 Dec;35(12):1488-92 - PubMed
    1. Eur J Pharmacol. 1998 Dec 4;362(2-3):261-6 - PubMed
    1. Sci China C Life Sci. 2007 Dec;50(6):739-47 - PubMed
    1. J Biol Chem. 1995 Feb 3;270(5):2107-11 - PubMed

Publication types

MeSH terms

LinkOut - more resources