Hypokalaemia is a clinical phenomenon in patients with acute myeloid l
eukaemia (AML) to which activation of the renin-angiotensin system (RA
S) may contribute. Recently monocytes were found to express renin, the
key initializing enzyme of the RAS. By RT/PCR, transcripts for renin
were detected in four of 18 bone marrow samples from patients with AML
. Three leukaemic cell lines, isolated monocytes, bone marrow stromal
cells and 25 peripheral blood and 24 bone marrow samples of normal con
trols were negative for renin transcripts. In view of the importance o
f local RAS in other tissues, the expression of renin in the bone marr
ow of AML patients warrants further investigation.