Peripheral electric stimulation inhibits morphine-induced place preference in rats.
Conditioned place preference (CPP) is a commonly used model to detect rewarding effect of drugs. To observe the effect of peripheral electric stimulation (PES) on morphine-induced CPP, we trained the rats with morphine in a CPP paradigm. Twelve hours before the testing phase, rats were given PES via stainless-steel needles with frequencies of 2, 100, or 2/100 Hz, respectively. PES of 2 and 2/100 Hz significantly decreased CPP in morphine-trained animals in a naloxone reversible manner, while PES of 100 Hz, foot shock, needle insertion, or plain restraining, showed no effect. Thus, PES with a low-frequency component (2 Hz) could specifically inhibit the expression of morphine-induced CPP, presumably via activation of opioid receptors.
Wang
B
B
Neuroscience Research Institute, Beijing Medical University, P.R. China.
Luo
F
F
Xia
Y Q
YQ
Han
J S
JS
D015670:Acupuncture Therapy / Q000379:methods*; D000701:Analgesics, Opioid / Q000494:pharmacology*; D000818:Animals; D003213:Conditioning, Psychological / Q000187:drug effects* / Q000502:physiology; D004305:Dose-Response Relationship, Drug; D008297:Male; D009020:Morphine / Q000494:pharmacology*; D009021:Morphine Dependence / Q000503:physiopathology / Q000628:therapy*; D010525:Peripheral Nerves / Q000502:physiology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013997:Time Factors; D004561:Transcutaneous Electric Nerve Stimulation
D000701:Analgesics, Opioid; D009020:Morphine