Specific binding of angiotensin II and atrial natriuretic factor in non-nephropathic type I diabetes mellitus.
We examined ten patients with type I diabetes mellitus and ten age- and sex-matched healthy controls. Median duration of diabetes was 7 years (range 0.5-24). None of the diabetic patients had hypertension, microalbuminuria, or proliferative retinopathy. Maximal specific binding capacity for angiotensin II to thrombocytes was significantly increased in diabetics (Bmax 11.9 +/- 1.6 sites per cell vs 7.0 +/- 0.9 in controls; P less than 0.01). In contrast, maximal binding for atrial natriuretic factor tended to be lower in type I diabetics (8.84 +/- 1.25 sites per cell vs 16.8 +/- 2.97; P less than 0.07). There was no difference of apparent dissociation constant (KD) for either receptor. Angiotensin II values (RIA) were greater in diabetics (16.2 +/- 1.5 pg/ml vs 8.5 +/- 1.4 in controls; P less than 0.02) and concentrations of atrial natriuretic factor (RIA) were not significantly different. The data suggest increased angiotensin II binding despite high angiotensin II concentrations in non-nephropathic type I diabetic patients. These findings may be relevant when considering the evolution of hypertension and microangiopathy lesions.
Mann
J F
JF
Department of Internal Medicine, University of Heidelberg, FRG.
Mürtz
H
H
Sis
J
J
Usadel
K H
KH
Hasslacher
C
C
Ritz
E
E
D000328:Adult; D000804:Angiotensin II / Q000097:blood*; D009320:Atrial Natriuretic Factor / Q000097:blood*; D001665:Binding Sites; D001792:Blood Platelets / Q000378:metabolism; D003922:Diabetes Mellitus, Type 1 / Q000097:blood*; D005260:Female; D006801:Humans; D007700:Kinetics; D008297:Male; D008875:Middle Aged
D000804:Angiotensin II; D009320:Atrial Natriuretic Factor