Anti-hypernociceptive and anti-oxidative effects of locally treated dobutamine in diabetic rats.

BACKGROUND: Oxidative stress as a significant factor in the development of diabetes induced neuropathic pain as well as the potential for prevention of this complication. Therefore, we hypothesized that locally administrated dobutamine, a beta-adrenoreceptor agonist, or esmolol, a beta-adrenoreceptor antagonist, can modulate the oxidative stress and ameliorate the diabetes induced neuropathic pain.

METHODS: Effects of locally (intraplantar) treated two pharmaceutical preparations used in clinical applications, dobutamine or esmolol, were investigated by measuring thermal latencies, mechanical thresholds and several oxidative stress parameters in streptozotocin (STZ) induced diabetic rats.

RESULTS: Diabetes induced hyperalgesia and allodynia more effectively relieved by dobutamine than esmolol. Anti-hypersensitive action of dobutamine continued through the experiment. Diabetes induced oxidative damage in the paw tissues since STZ rats showed significant increased malondialdehyde (MDA), nitric oxide (NO) and decreased superoxide dismutase (SOD), catalase (CAT), myeloperoxidase (MPO) in the paw. Dobutamine, but not esmolol, restored the tissue oxidative and nitrossive stress parameters to those observed in the non-diabetic rats.

CONCLUSIONS: Findings suggest that diabetes-induced oxidative stress may be partially responsible for the development of diabetic neural complications. Amelioration of oxidative stress by locally treated dobutamine can be beneficial in diabetes induced neuropathic pain.