Modulation of arachidonic acid-evoked cardiorespiratory effects by the central lipoxygenase pathway

We previously reported that intracerebroventricularly (ICV) injected arachidonic acid (AA) could produce pressor and bradycardic responses on the cardiovascular system and hyperventilation effect on the respiratory system by activating cyclooxygenase (COX). We also demonstrated that centrally injected AA-induced cardiovascular and respiratory responses were mediated by COX-metabolites, such as thromboxane A(2) (TXA(2)), prostaglandin (PG) D, PGE, and PGF(2 alpha). Brain tissue is also able to express the lipoxygenase (LOX) enzyme and LOX-induced AA-metabolites. The current study was designed to investigate the possible mediation of the central LOX pathway in AA-induced cardiorespiratory effects in anesthetized rats.