A Stibal | PubMed Health

PubMed2007

[Surgery for Parkinson's disease].

Surgery for Parkinson's Disease (PD) is being increasingly used. The main reason for this renewal in surgical treatment for PD is the "deep brain stimulation" (DBS) that replaced the previously used stereotactic lesions in most centers. DBS allows a focal specific electrical stimulation of basal ganglia target instead of an irreversible lesion. Mainly bilateral DBS of the nucleus subthalamicus is now an established surgical treatment for PD. But DBS of the Globus pallidus internus and of the thalamus should still be considered in selected patients. DBS is an efficient treatment for motor complication of PD that can no longer be controlled by drug treatment. Dyskinesia, bradykinesia, tremor and rigor can be improved by DBS and the medication can be reduced. It is still unclear, however, how the improvement in motor symptoms affects quality of life in the long term. Furthermore, patients with severe cognitive and psychiatric symptoms as well as patients with severe axial symptoms should not be operated since these symptoms may worsen after surgery.

Deep Brain Stimulation↗

PubMed1999

Spinal blockade of opioid receptors prevents the analgesia produced by TENS in arthritic rats.

Transcutaneous electrical nerve stimulation (TENS) is commonly used for relief of pain. The literature on the clinical application of TENS is extensive. However, surprisingly few reports have addressed the neurophysiological basis for the actions of TENS. The gate control theory of pain is typically used to explain the actions of high-frequency TENS, whereas, low-frequency TENS is typically explained by release of endogenous opioids. The current study investigated the role of mu, delta, and kappa opioid receptors in antihyperalgesia produced by low- and high-frequency TENS by using an animal model of inflammation. Antagonists to mu (naloxone), delta (naltrinodole), or kappa (nor-binaltorphimine) opioid receptors were delivered to the spinal cord by microdialysis. Joint inflammation was induced by injection of kaolin and carrageenan into the knee-joint cavity. Withdrawal latency to heat was assessed before inflammation, during inflammation, after drug (or artificial cerebral spinal fluid as a control) administration, and after drug (or artificial cerebral spinal fluid) administration + TENS. Either high- (100 Hz) or low- frequency (4 Hz) TENS produced approximately 100% inhibition of hyperalgesia. Low doses of naloxone, selective for mu opioid receptors, blocked the antihyperalgesia produced by low-frequency TENS. High doses of naloxone, which also block delta and kappa opioid receptors, prevented the antihyperalgesia produced by high-frequency TENS. Spinal blockade of delta opioid receptors dose-dependently prevented the antihyperalgesia produced by high-frequency TENS. In contrast, blockade of kappa opioid receptors had no effect on the antihyperalgesia produced by either low- or high-frequency TENS. Thus, low-frequency TENS produces antihyperalgesia through mu opioid receptors and high-frequency TENS produces antihyperalgesia through delta opioid receptors in the spinal cord.

Animals↗