buprenorphine and Brain-Ischemia

Laboratory mice constitute an extensively used model to study the pathologic and functional outcomes of cerebral ischemic stroke. The middle cerebral artery occlusion (MCAO) model requires surgical intervention, which potentially can result in postsurgical pain and stress. In the present study, we investigated whether buprenorphine and meloxicam, at clinically relevant doses provided pain relief without altering infarct volume in male C57BL/6 mice. Common known side-effects of buprenorphine, including decreased food consumption, were noted after surgery in buprenorphine-treated mice, but these effects were brief and seen only during the treatment period. Fecal corticosterone metabolites did not differ significantly between the groups. In the present study, buprenorphine treatment did not alter infarction volume when compared with that of mice that did not receive analgesia. In contrast, meloxicam treatment significantly reduced infarct volume and may be a confounder if used as an analgesic during MCAO surgery. Furthermore, investigation of behavioral profiles by using an automated behavioral scoring system showed that rearing and sniffing behaviors decreased as infarct volume increased. This suggests that studies of exploratory behavior may aid in developing new markers of short-term stroke-related behavioral deficiencies in laboratory mice.

Topics: Analgesics; Animals; Brain Ischemia; Buprenorphine; Corticosterone; Infarction, Middle Cerebral Artery; Male; Meloxicam; Mice; Mice, Inbred C57BL; Pain; Pain Management; Research Design; Thiazines; Thiazoles

Drug users who crush, dissolve, and inject buprenorphine tablets parenterally may be at risk of severe thromboembolic complications or death. We describe patients with neurologic complications after injecting buprenorphine tablets.. Brain MRI including diffusion-weighted imaging (DWI) in patients admitted to the neurologic department after injecting buprenorphine tablets were reviewed.. Seven men had neurologic complications after buprenorphine tablet injection. In 5 patients, multiple small scattered hyperintense lesions were detected on DWI in the cortex, white matter, and basal ganglia of the cerebral hemisphere; one patient had a single small lesion. The side of MRI abnormality corresponded to the side of needle marks on the neck except in one patient who had bilateral injections. One patient, who denied injecting into the neck, had DWI abnormalities in the middle cerebral artery territory on one side and occlusion of the ipsilateral internal carotid artery.. Buprenorphine tablets can be intentionally or inadvertently injected into the carotid artery, causing a characteristic appearance on diffusion-weighted imaging, consistent with embolic cerebral infarction.

Topics: Adult; Brain Ischemia; Buprenorphine; Drug Users; Humans; Injections; Magnetic Resonance Imaging; Male; Middle Aged; Narcotics; Stroke; Thromboembolism

Buprenorphine has been increasingly used as maintenance therapy in opioid dependence as an alternative to methadone and other pharmacological therapies. However, available data suggest increased risk of cerebrovascular events in opioid-dependent patients. Therefore, an opioid that provides safety with regard to neurological function should be considered by opioid-dependent patients. The evidence for the in vitro neurotoxic effects of buprenorphine is rapidly increasing. In order to clarify whether buprenorphine is also neurotoxic under the condition of cerebral ischemia in vivo, we applied an acute dose of buprenorphine in a transient model of focal cerebral ischemia in rats. Our study provides preclinical evidence for the usage of buprenorphine during the postoperative period following ischemic events as well as for the maintenance therapy of opioid-dependent patients wherein the risk of cerebrovascular events is increased.

Topics: Animals; Brain Ischemia; Buprenorphine; Cerebral Infarction; Disease Models, Animal; Drug Evaluation, Preclinical; Laser-Doppler Flowmetry; Male; Narcotic Antagonists; Rats; Rats, Wistar