![]() |
| An obviously photoshopped picture of a bottle of Cardizem |
![]() |
| Cardizem (Diliazem) |
L-TYPE CA2+CHANNELS are multisubunit, transmembrane proteins controlling Ca2+ influx into cells and play a pivotal role in the physiological regulation of the cardiac, vascular, endocrine and central nervous system. Alterations in the density or function of L-type Ca2+ channels have been implicated in a variety of diseases, including atrial fibrillation (1 , 2) , ventricular hypertrophy (3) , and heart failure (4) . In the heart, the L-type Ca2+ channel is composed of the pore-forming α1C subunit (Cav1.2a) and the auxiliary subunits α2δ and β2 (reviewed in ref 5 ). A crucial signaling pathway that regulates the heart beat is the sympathetic stimulation of Ca2+ channel activity, which increases the amplitude of the Ca2+ inward current (ICaL), leads to a leftward shift in current-voltage relationship and a slowing of channel inactivation (reviewed in ref 6 ). These effects are believed to result from PKA-mediated phosphorylation of the channel subunits α1C (7 , 8) and β2 (9 , 10) or still undefined associated proteins (11) . In a previous attempt to define the molecular details of Ca2+ channel phosphorylation in response to the sympathetic agonist, isoprenaline, we identified ahnak, a 700 kDa PKA substrate (5643 aa) as Ca2+ channel-associated protein (12) .
.


No comments:
Post a Comment