Calcium influx via the L-type voltage-gated Ca1.2 calcium channel in smooth muscle cells regulates vascular contraction. Calcium channel blockers (CCBs) are widely used to treat hypertension by inhibiting Ca1.2 channels. Using the vascular smooth muscle cell line, A7r5 and primary culture of cerebral vascular smooth muscle cells, we found that the expression and function of Ca1.2 channels are downregulated during hypoxia. Furthermore, hypoxia induces structural changes in Ca1.2 channels via alternative splicing. The expression of exon 9* is upregulated, whereas exon 33 is downregulated. Such structural alterations of Ca1.2 channels are caused by the decreased expression of RNA-binding proteins RNA-binding protein fox-1 homolog 1 and 2 (RbFox1 and RbFox2). Overexpression of RbFox1 and RbFox2 prevents hypoxia-induced exon 9* inclusion and exon 33 exclusion. Importantly, such structural alterations of the Ca1.2 channel partly contribute to the enhanced sensitivity of Ca1.2 to isradipine (a CCB) under hypoxia. Overexpression of RbFox1 and RbFox2 successfully reduces isradipine sensitivity in hypoxic smooth muscle cells. Our results suggest a new strategy to manage ischemic diseases such as stroke and myocardial infarction.