Central hypoxaemia in rats provokes neurological defects similar to those seen in experimental diabetes mellitus: evidence for a partial role of endoneurial hypoxia in diabetic neuropathy.
Endoneurial hypoxia has been put forward as a factor contributing to diabetic neuropathy. The aim of this study was to determine whether alterations in motor nerve conduction velocity, Na+/K(+)-ATPase activity and substance P content of nerve and skin tissue, characteristic of the diabetic rat, could develop in non-diabetic animals subjected to a central hypoxaemia for five weeks. Compared to normoxic controls, five weeks of central hypoxaemia caused a fall in motor nerve conduction velocity of 30% (P less than 0.01), a decrease in sciatic nerve substance P content (68%; P less than 0.001) combined with elevated substance P content per unit area foot skin (44%; P less than 0.01). This pattern of change is qualitatively similar to that seen in diabetic rats. The Na+/K(+)-ATPase activity, however, was unaltered by the hypoxic environment. These findings support strongly a partial role for hypoxia in the pathogenesis of diabetic neuropathy.
Smith
W J
WJ
Department of Pharmacology, Queen Mary and Westfield College, London, U.K.
Diemel
L T
LT
Leach
R M
RM
Tomlinson
D R
DR
D000818:Animals; D003929:Diabetic Neuropathies / Q000503:physiopathology*; D005947:Glucose / Q000032:analysis; D000860:Hypoxia / Q000150:complications*; D007294:Inositol / Q000032:analysis; D008297:Male; D009419:Nerve Tissue Proteins / Q000032:analysis; D009431:Neural Conduction; D010523:Peripheral Nervous System Diseases / Q000209:etiology* / Q000503:physiopathology; D051381:Rats; D011919:Rats, Inbred Strains; D012584:Sciatic Nerve / Q000737:chemistry; D012867:Skin / Q000737:chemistry; D000254:Sodium-Potassium-Exchanging ATPase / Q000032:analysis; D013373:Substance P / Q000032:analysis
D009419:Nerve Tissue Proteins; D013373:Substance P; D007294:Inositol; D000254:Sodium-Potassium-Exchanging ATPase; D005947:Glucose