Enzymes that hydrolyze adenine nucleotides in diabetes and associated pathologies.
The activities of the enzymes NTPDase (E.C. 3.6.1.5, apyrase, ATP diphosphohydrolase, ecto-CD39) and 5'-nucleotidase (E.C. 3.1.3.5, CD73) were analyzed in platelets of type 2 diabetic, hypertensive and type 2 diabetic/hypertensive patients. The results showed an increase in platelet NTPDase activity in type 2 diabetic (34% and 72%), hypertensive (32% and 70%) and type 2 diabetic/hypertensive patients (30% and 55%) when compared to control (P<.01) with ATP and ADP as substrate, respectively. 5'-Nucleotidase activity was elevated in the hypertensive (60%) and type 2 diabetic/hypertensive (53%) groups when compared to the control and type 2 diabetic group (P<.01). No differences in sensitivity to inhibitors was detected between the platelets of controls and type 2 diabetic/hypertensive patients. No effects on the enzyme activities were observed when pharmacological doses of propranolol, captopril, furosemide, chlorpropamide, acetylsalicylic acid and glibenclamide were administered. Furthermore, changes in platelet adhesiveness and reactivity were found in all groups tested. In conclusion, we may postulate that NTPDase and 5'-nucleotidase from platelets are altered in patients with type 2 diabetes and hypertension. Probably, such alterations are involved in compensatory physiological responses in these diseases and are related to other important mechanisms of thromboregulation.
Lunkes
Gilberto Inácio
GI
Departamento de Química, Centro de Ciências Naturais e Exatas, Universidade Federal de Santa Maria, 97105-900, Santa Maria, RS, Brazil.
Lunkes
Daniela
D
Stefanello
Francieli
F
Morsch
André
A
Morsch
Vera Maria
VM
Mazzanti
Cinthia Melazzo
CM
Schetinger
Maria Rosa Chitolina
MR
D015720:5'-Nucleotidase / Q000378:metabolism*; D000227:Adenine Nucleotides / Q000378:metabolism*; D000251:Adenosine Triphosphatases / Q000378:metabolism*; D000328:Adult; D000959:Antihypertensive Agents / Q000494:pharmacology; D001780:Blood Coagulation Tests; D001792:Blood Platelets / Q000201:enzymology; D016022:Case-Control Studies; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000150:complications / Q000201:enzymology*; D005260:Female; D006801:Humans; D006868:Hydrolysis; D006973:Hypertension / Q000097:blood / Q000201:enzymology* / Q000209:etiology; D007004:Hypoglycemic Agents / Q000494:pharmacology; D008297:Male; D008875:Middle Aged; D010979:Platelet Function Tests
D000227:Adenine Nucleotides; D000959:Antihypertensive Agents; D007004:Hypoglycemic Agents; D015720:5'-Nucleotidase; D000251:Adenosine Triphosphatases