ABUNDANT EXPRESSION OF THROMBOXANE SYNTHASE IN RAT MACROPHAGES

The cloned cDNA for rat thromboxane (TX) synthase with a size of 1851 bp contained a 1599-bp open reading frame which encoded a 533-amino ac id protein sharing 79.7% identity with human TX synthase. RNA blot ana lysis was carried out with rat cells and tissues. Rat peritoneal macro phages most abundantly expressed mRNA for TX synthase, and its level w as not changed by in vivo stimulation of casein. Bone marrow, spleen, lung and thymus also expressed the TX synthase gene. These findings su ggest the possibility that TXA(2) plays a role in the immune system.