The Blood Pressure Lowering Effect of 20-HETE Blockade in Cyp4a14(-/-) Mice is associated With Natriuresis
20-Hydroxy-5,8,11,14-eicosatetraenoic acid (20-HETE) has been linked to pro- and anti-hypertensive actions through its ability to promote vasoconstriction and inhibit Na transport in the ascending limb of the loop of Henle, respectively. In this study, we assessed the effects of 20-HETE blockade on blood pressure, renal hemodynamics and urinary sodium excretion in Cyp4a14(-/-) male mice, which display androgen-driven 20-HETE-dependent hypertension. Administration of 20-SOLA, a water-soluble 20-HETE antagonist, in the drinking water normalized blood pressure of male Cyp4a14(-/-) hypertensive mice (124+/- vs 153+/- mmHg) while having no effect on age-matched normotensive wild-type male mice. Hypertension in Cyp4a14(-/-) male mice was accompanied by decreased renal perfusion and reduced glomerular filtration rates which were corrected by treatment with 20-SOLA. Interestingly, Cyp4a14(-/-) male mice treated with 20-SOLA displayed increased urinary sodium excretion that paralleled by the reduction of blood pressure suggestive of an anti-natriuretic activity of endogenous 20-HETE in the hypertensive mice. This interpretation is in line with the observation that the natriuretic response to acute isotonic saline loading in hypertensive Cyp4a14(-/-) male mice was significantly impaired relative to that in WT mice; this impairment was corrected by 20-SOLA treatment. Hence, endogenous 20-HETE appears to promote sodium conservation in hypertensive Cyp4a14(-/-) male mice, presumably, as a result of associated changes in renal hemodynamics and/or direct stimulatory action on tubular sodium reabsorption.
Pandey, V., Garcia, V., Gilani, A., Mishra, P., Zhang, F., Paudyal, M., Falck, J., Nasjletti, A., Wang, W., & Schwartzman, M. (2017). The Blood Pressure Lowering Effect of 20-HETE Blockade in Cyp4a14(-/-) Mice is associated With Natriuresis. The Journal of Pharmacology and Experimental Therapeutics, 363 (3), 412-418. https://doi.org/10.1124/jpet.117.243618