MRL lpr/lpr (MRL/l) mice exhibit a disease similar to
systemic lupus erythematosus (SLE) in humans. To investigate the influence of
antihypertensive treatment on this disease, four groups of MRL/l mice were treated with the
angiotensin-converting enzyme inhibitor captopril (n = 25), with the sympathetic blocker
bretylium (n = 15), and with
cyclophosphamide (n = 10). Thirty-five mice did not receive any treatment and served as controls. Survival rate, blood pressure, incidence of
proteinuria and
hematuria, renal pathology, lymphoid
hyperplasia and
dermatitis were studied. The survival at the age of 36 weeks was significantly improved by
captopril as compared to controls (60 vs. 25%, p = 0.035). The
cyclophosphamide group showed no mortality at that time and the
bretylium group did not differ from the control group.
Captopril and
bretylium reduced systolic blood pressure significantly while
cyclophosphamide was without effect.
Captopril and
cyclophosphamide diminished significantly the glomerular damage with less proliferative changes and a decreased incidence of
proteinuria. The
bretylium-treated animals also exhibited an improved renal pathology index but they did not differ from the controls with respect to
proteinuria and
hematuria. Lymphoid
hyperplasia and
dermatitis were decreased only by
captopril and
cyclophosphamide. It is concluded that
captopril improves survival in SLE disease of MRL/l mice, counteracting lymphoid
hyperplasia, renal disease,
dermatitis and decreasing arterial blood pressure.