The effect of metabolic regulation on microvascular permeability to small and large molecules in short-term juvenile diabetics.
The microvascular permeability to small and large molecules was studied during good and poor metabolic regulation in ten short duration juvenile diabetics. The following variables were measured; daily urinary albumin and beta2-microglobulin-excretion rates, whole body transcapillary escape rate of albumin (TER), glomerular filtration rate (GFR), capillary filtration coefficient (CFC), and capillary diffusion capacity (CDC). The urinary albumin and beta2-microglobulin concentration were measured by sensitive radioimmunoassays; TER was detemined from the initial disappearance of intravenously injected 125I-labelled human serum albumin; GFR was measured on the forearm by straingauge plethysmography and CDS for 51Cr-EDTA clearance; CFC was measured on the forearm by straingauge plethysmography and CDC, for 51Cr-EDTA was determined in the jyperaemic anterio tibial muscle by the local clearance technique. All the above mentioned variables, except CDC, were significantly increased during poor metabolic regulation, indicating a functional microangiopathy. The mechanisms of these alterations appear to be increased filtration pressure in the microcirculation and/or increased porosity of the microvasculature. The findings of increased microvascular albumin passage are compatible with the hypothesis that the organic - histologicallly demonstrated - diabetic microangiopathy is a long-term effect of periods of increased extravasation of plasma proteins, with subsequent protein deposition in the microvascular wall, i.e. the concept to plasmatic vasculosis.
D000293:Adolescent; D000328:Adult; D002199:Capillary Permeability; D003922:Diabetes Mellitus, Type 1 / Q000188:drug therapy / Q000503:physiopathology*; D003925:Diabetic Angiopathies / Q000188:drug therapy / Q000503:physiopathology*; D003928:Diabetic Nephropathies / Q000503:physiopathology; D005260:Female; D005919:Glomerular Filtration Rate; D006801:Humans; D007328:Insulin / Q000627:therapeutic use; D008297:Male; D011507:Proteinuria; D012709:Serum Albumin / Q000378:metabolism
D007328:Insulin; D012709:Serum Albumin