Polyunsaturated fatty acid synthesis de novo is required for calcium release in vascular smooth muscle

<p>Previous studies show that inhibition of delta-5 desaturase and delta-6 causes a<br>decrease in phenylepherine (PE)- induced vasoconstriction in human femoral artery,<br>and in rat aorta and mesenteric arteries. These data showed that the activity of the<br>polyunsaturated fatty acid (PUFA) biosynthesis pathway related to vasoconstriction is<br>specifically located in vascular smooth muscle (VSM). The study also showed that<br>inhibiting the PUFA-biosynthesis pathway causes a decrease in the release of the proconstriction<br>eicosanoids prostaglandin (PG) F2 alpha, PGE2 and thromboxane A2 (1).<br>Activity of the PUFA biosynthesis pathway has previously been shown in arterial<br>endothelial (2) and smooth muscle cells (3). However, there is no direct evidence of the<br>exact extent of the pathway and contribution of PUFA biosynthesis to vascular function<br>in VSM is currently unknown.