Prostaglandin alterations in barely hypertensive Dahl S rats

In summary, prostacyclin, PGE2, and PGD2 are vasodilators and had significantly lower renal cortical and outer medullary concentrations in the borderline hypertensive S rats compared to normotensive R rats. Conversely, thromboxane is a vasoconstrictor which had significantly higher renal cortical and outer medullary concentrations in borderline hypertensive S rats compared to normotensive R rats. Thus, in borderline hypertensive S rats, both renal cortex and outer medulla have a prostaglandin pattern which favors vasoconstriction in cortical vessels and in descending vasa recta. This could partially account for the increased renal vascular resistance and low papillary plasma flows which are integral components of Dahl hypertension. The low PGE2 in S kidneys would also enhance Na reabsorption in collecting tubules and ascending limbs, thereby encouraging Na retention and hypertension.