Continuous buprenorphine delivery effect in streptozotocine-induced painful diabetic neuropathy in rats.
Diabetic peripheral neuropathy (DPN) can induce loss of nociception as well as mechanical hyperalgesia and tactile allodynia. Pharmacological and clinical studies have shown that buprenorphine, a low-molecular-weight, lipophilic, opioid analgesic available as a transdermal matrix patch formulation, acts on neuropathic pain. To assess the role of buprenorphine in the treatment of DPN-associated neuropathic pain, we used a well-established experimental rat model of DPN in which buprenorphine at doses of 1.2 and 2.4 microg/kg/h was administered by implantable Alzet osmotic pumps for 3 weeks. After 6 weeks of diabetes, nerve conduction velocity (NCV) and behavioural responses to noxious mechanical and thermal stimuli were assessed. Diabetic rats showed an impairment of NCV, mechanical allodynia, and thermal hypoalgesia. Both doses of buprenorphine significantly reversed the diabetes-induced allodynia up to day 7 of treatment. Buprenorphine did not alter either thermal perception or NCV.


CONCLUSIONS
This study evaluated, through a multimodal approach, the analgesic effect of buprenorphine in an experimental rat model of painful DPN. Our results suggest a possible role for buprenorphine in the management of DPN-associated neuropathic pain.
Canta
Annalisa
A
Department of Neuroscience and Biomedical Technologies, University of Milan Bicocca, Milan, Italy. annalisa.canta@unimib.it
Chiorazzi
Alessia
A
Meregalli
Cristina
C
Carozzi
Valentina
V
Oggioni
Norberto
N
Lauria
Giuseppe
G
Lombardi
Raffaella
R
Bianchi
Roberto
R
Porretta-Serapiglia
Carla
C
Cavaletti
Guido
G
D000200:Action Potentials / Q000187:drug effects / Q000502:physiology; D000701:Analgesics, Opioid / Q000008:administration & dosage; D000818:Animals; D002047:Buprenorphine / Q000008:administration & dosage / Q000494:pharmacology*; D003921:Diabetes Mellitus, Experimental / Q000150:complications; D003929:Diabetic Neuropathies / Q000188:drug therapy* / Q000378:metabolism / Q000503:physiopathology; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D004334:Drug Administration Schedule; D004568:Electrodiagnosis; D006930:Hyperalgesia / Q000188:drug therapy / Q000378:metabolism / Q000503:physiopathology; D015918:Infusion Pumps, Implantable; D008297:Male; D009431:Neural Conduction / Q000187:drug effects / Q000502:physiology; D017933:Peripheral Nervous System / Q000187:drug effects* / Q000378:metabolism / Q000503:physiopathology; D051381:Rats; D017207:Rats, Sprague-Dawley; D016896:Treatment Outcome
D000701:Analgesics, Opioid; D002047:Buprenorphine