Effects of Atipamezole and Naloxone on Electroencephalographic Spectral Edge Frequency 95 in Dogs Sedated by Acupuncture at GV20 and Yintang Point

The purpose of this study was to evaluate the antagonism of acupuncture-induced sedation by electroencephalographic spectral edge frequency (SEF) 95 in 10 healthy intact male Miniature Schnauzer dogs (4.2-6.1kg; 2-3 years old) without neurological disorder. The GV20 and Yintang acupoints were administered for 20 min. While the dogs were conscious, SEF 95 baseline values were recorded at 2-min intervals for 4 min. Then acupuncture was administered at the GV20 and Yintang acupoints. During the acupuncture procedure, the SEF 95 values were recorded at 2-min intervals for 10 min. Subsequently, antagonist drugs, naloxone and atipamezole, were administered through the cephalic vein. The SEF 95 values were then measured again at 2-min intervals for 10 min. Those values were found to be significantly increased after administration of atipamezole in dogs sedated by acupuncture at the GV20 and Yintang acupoints (p<0.05). However, the SEF 95 values in the naloxone groups did not show any significant changes before and after administration of the antagonist. It was concluded that sedation induced by acupuncture at the GV20 and Yintang acupoints might be partially associated with the alpha(2)-adrenergic system.