passages.id: split_4_test_1533_passage
passages.type: progene_text
passages.text: After 4 hours of incubation of HUVEC with Bk ( 10 nM ) it induced mRNAs for haemooxygenase 1 ( HO-1 ) , cyclooxygenase 2 ( COX-2 ) , prostaglandin E synthase ( PGE-S ) whereas mRNA for nitric oxide synthase 2 ( NOS-2 ) was weakly affected .