Decreased calcium channel currents and facilitated epinephrine release in the Ca2+ channel beta 3 subunit-null mice

作者：Ohta Toshio; Ohba Takayoshi; Suzuki Takashi; Watanabe Hiroyuki; Sasano Hironobu; Murakami Manabu^*

来源：Biochemical and Biophysical Research Communications, 2010, 394(3): 464-469.

DOI：10.1016/j.bbrc.2010.01.036

• Calcium channels
• Beta subunit
• Mouse
• Epinephrine
• Catecholamine
• Sympathetic tonus

The beta subunits of voltage-dependent calcium channels are known to modify calcium channel currents through pore-forming alpha 1 subunits The beta 3 subunit is expressed in the adrenal gland and participates in forming various calcium channel types We performed a series of experiments in beta 3-null mice to determine the role of the beta 3 subunit in catecholamine release from the adrenal chromaffin system
Protein levels of N-type channel forming CaV2 2 and L-type forming CaV1 2 decreased The beta 3-null mice showed a decreased baroreflex, suggesting decreased sympathetic tonus, whereas plasma catecholamine levels did not change. Pulse-voltage stimulation revealed significantly increased amperometrical currents in beta 3-null mice, while patch-clamp recordings showed a significant reduction in Ca2+-currents due to reduced L- and N-type currents, indicating facilitated exocytosis A biochemical analysis revealed increased InsP3 production
In concl

• 出版日期2010-4-9