RELATION BETWEEN PANCREATIC-ISLET CELLULAR INFILTRATION AND PLASMA-FIBRINOGEN OR ALPHA-1-ACID GLYCOPROTEIN LEVELS IN SPONTANEOUSLY AND STREPTOZOTOCIN-DIABETIC RATS - AN INCREASE IN THESE PROTEIN-LEVELS IS NOT NECESSARY FOR INDUCING MICROCIRCULATORY ERYTHROCYTE VELOCITY ALTERATION

Plasma levels of fibrinogen, alpha1-acid glycoprotein (AG) and albumin , pancreatic insulitis quantitative scores, and erythrocyte velocity i n the mesoappendix microvessels were measured in BB diabetic (BBD) and streptozotocin-diabetic rats (WSTZ) in order to answer the following questions: (a) Does hypertibrinogenemia or increase in AG plasma level occur in BBD and WSTZ rats, and if so, are these alterations secondar y to the hyperglycemia or to an inflammatory process such as insulitis ? (b) Is there a decrease in microcirculatory flow in the BBD and WSTZ rats, and if so, is it secondary to the hyperfibrinogenemia and/or th e hyperglycemia) Insulitis was present in the BBD rats after 5 weeks o f disease (with a score of 2.9 +/- 0.1 vs. 1.4 +/- 0.6 in the normogly cemic controls), but absent in WSTZ rats after 5 months of disease (1. 2 +/- 0.06 vs. 1.1 +/- 0.06). Increase in fibrinogen and AG plasma lev els was observed in the BBD rats only and appears linked to the insuli tis. The major acute phase protein AG level is increased in BBD rats a lready on the first day of appearance of glycosuria. In the WSTZ rats, without insulitis, chronic hyperglycemia alone did not induce an incr ease in fibrinogen and AG plasma levels. A decreased microcirculatory erythrocyte velocity has been found in both BBD and WSTZ rats. Thus an increase in fibrinogen or AG plasma levels is not necessary for induc ing a decrease in erythrocyte velocity. Hyperglycemia is probably the main factor responsible for the decrease in microcirculatory flow in t he BBD and WSTZ rats.