Strength-duration properties in diabetic polyneuropathy.

Abstract

We sought to examine the changes in the strength-duration time constant (SDTC) of the median nerve in diabetic polyneuropathy. The SDTC is a measure of axonal excitability and depends on the biophysical properties of the axonal membrane. It may provide some information about Na(+) channel functioning. Forty-nine diabetic patients (30 men, 19 women; mean age, 54.6+/-9.4 years) and 15 age-matched healthy subjects (11 men, 4 women; mean age, 53.1+/-7.6 years) participated in the study. SDTC and rheobase values were 384.5+/-97.9 micros and 4.6+/-2.4 mA in patients and 313.8+/-46.7 micros and 6.0+/-2.6 mA in controls. The SDTC was found to be significantly different between the two groups (P=.009 for SDTC and P=.066 for rheobase). Fasting glucose and HbA1c levels of patients were 206.6+/-88.7 mg/dL and 8.8+/-2.4%, and these were not correlated with SDTC or rheobase (P<.05). We suggest that longer SDTC, indicating increased axonal excitability may develop in patients with polyneuropathy associated with uncontrolled diabetes.

• Authors: Deniz Yerdelen, Filiz Koç, Hilmi Uysal, Yakup Sarica
• Journal: Diabetes research and clinical practice (Diabetes Res Clin Pract) Vol. 78 Issue 1 Pg. 56-9 (Oct 2007) ISSN: 0168-8227 [Print] Ireland
• PMID: 17408800 (Publication Type: Journal Article)

Chemical References

• Sodium Channels
• Sodium-Potassium-Exchanging ATPase

Topics

• Diabetic Neuropathies (physiopathology)
• Female
• Humans
• Male
• Median Nerve (physiopathology)
• Middle Aged
• Muscle Strength (physiology)
• Polyneuropathies (physiopathology)
• Reference Values
• Sodium Channels (physiology)
• Sodium-Potassium-Exchanging ATPase (metabolism)
• Sural Nerve (physiopathology)