Effect of the serine-borate complex on the relative ability of leukotriene C 4, D 4 and E 4 to inhibit lung and brain [ 3H]leukotriene D 4 and [ 3H]leukotriene C 4 binding: Demonstration of the agonists' potency order for leukotriene D 4 and leukotriene C 4 receptors

Abstract

To define the potency order of the leukotrienes for inhibition of [3H] leukotriene D4 and [3H] leukotriene C4 binding, we investigated leukotriene C4, D4 and E4 competition with and without the serine-borate complex in guinea pig lung and brain homogenates. Without it, the rank order of their potency for inhibition of lung [3H] leukotriene D4 or [3H] leukotriene C4 binding was leukotriene C4 = leukotriene D4 greater than leukotriene E4. Presence of the complex altered the potency order for both competition studies: for the [3H] leukotriene D4 competition it was leukotriene D4 greater than leukotriene E4 = leukotriene C4 and for the [3H] leukotriene C4 competition it was leukotriene C4 much greater than leukotriene D4 greater than or equal to leukotriene E4.