Nerve regeneration and serum levels of insulin-like growth factor-I in rats with streptozotocin-induced insulin deficiency

• Peripheral nerve regeneration was studied in female Sprague-Dawley rats with streptozotocin-induced insulin deficiency. Nerve regeneration was provoked by a crush lesion on the sciatic nerve 21 days after the streptozotocin injection. The regeneration was assessed by a pinch test at different time-points after injury. The rate ofregeneration in insulin-deficient animals, 2.5 mm/day, was significantly lower than in control animals, 2.9 mm/day(P < 0.05). There was no difference in the initial delay, i.e. the period before regeneration attains a constant velocity. One group of insulin-deficient rats was treated with insulin during the regeneration period by means of implanted osmotic mini-pumps. This treatment prevented the decrease in regenerationsw. After 6 days the sciatic nerves of insulin-deficient rats had regenerated 12.3 ±0.3 mm (mean ±S.E.M.), while the corresponding value for insulin-treated rats was 15.7 ±0.6 mm (P > 0.01). The streptozotocin-treated rats were found to have a 39% reduction in the serum level of insulin-like 1 growth factor-I (IGF-I)_compared to control rats (0.33 ± 0.22 μg/ml and 0.54 ± ml respectively, (P < 0.001). Insulin treatment 1830 1732 during the regeneration period completely restored the IGF-I level back to normal.

Subject headings

NATURVETENSKAP  -- Biologi -- Cellbiologi (hsv//swe)

NATURAL SCIENCES  -- Biological Sciences -- Cell Biology (hsv//eng)

MEDICIN OCH HÄLSOVETENSKAP  -- Medicinska och farmaceutiska grundvetenskaper -- Neurovetenskaper (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Basic Medicine -- Neurosciences (hsv//eng)

Keyword

Diabetes

Insulin

Insulin-like growth factor-I

Nerve regeneration

Rat

Sciatic nerve

Somatomedin

Streptozotocin

Publication and Content Type

art (subject category)

ref (subject category)