Reversal of cerebrovascular endothelial dysfunction in diabetes: the effect of allopurinol upon cerebrovascular nitric oxide bioavailability

Status

Active, not recruiting

Phases

Unknown

Study type

Interventional

Source

ISRCTN

Registry ID

ISRCTN68849312

Enrollment

Registered

2005-11-22

Start date

2005-11-01

Completion date

Unknown

Last updated

2015-01-13

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Diabetes Nutritional, Metabolic, Endocrine Diabetes

Interventions

Two weeks allopurinol versus lactose capsule.

Eligibility

Sex/Gender

All

Inclusion criteria

Inclusion criteria: 1. Type II diabetes less than 5 years duration, treated with diet, metformin thiazolidinediones or a combination 2. Aged greater than 40 years 3. Normal full Bruce protocol exercise treadmill testing (ETT) 4. Favourable temporal bony window 5. HbA1c less than 9% 6. Cholesterol less than 7.5 mmol/l

Exclusion criteria

Exclusion criteria: 1. Greater than 70% Internal carotid artery stenosis 2. Known coronary artery disease 3. Other significant comorbidity 4. Contraindication to allopurinol 5. Concurrent therapy with azathioprine or 6-mercaptopurine 6. Insulin or sulphonylurea treatment 7. Serum creatinine greater than 250 µmol/l

Design outcomes

Primary

Measure	Time frame
The change in internal carotid artery flow following L-NMMA infusion.	—

Secondary

Measure	Time frame
1. Change in serum urate level 2. Change in middle cerebral artery flow velocity	—

Countries

United Kingdom

Outcome results

None listed

Source: ISRCTN (via WHO ICTRP) · Data processed: Feb 4, 2026