%0 Journal Article %T Effects of xylazole on heart rate and blood pressure in conscious dogs %A Rong Yao-fang %A Hsu Walter H %A Hembrough Frederick B %J Acta Pharmacologica Sinica %D 2016 %B 2016 %9 %! Effects of xylazole on heart rate and blood pressure in conscious dogs %K %X Xylazole (Xyl) is an analogue of xylazine (Xyn) synthesized by Lanzhou Institute of Chinese Traditional Veterinary Medicine. The effects of Xyl on heart rate and blood pressure were studied in 5 conscious dogs. Xyl 1 mg/kg iv was similar to Xyn in producing bradycardia and an initial transient hypertension followed by a lasting hypotension which was less significant than Xyn. Yohimbine (0.1 and 0.3 mg/kg), an alpha 2-adrenoreceptor blocking agent, antagonized bradycardia and hypotension induced by Xyl. Tolazoline (3.3 mg/kg), a nonselective alpha-adrenoreceptor blocking agent, reversed the bradycardia and hypotensive effect. Prazosin (1 mg/kg), an alpha 1-adrenoreceptor blocking agent, did not change Xyl-induced bradycardia and hypotension. Atropine (20 micrograms/kg) not only antagonized Xyl-induced bradycardia but also changed from bradycardia to tachycardia, and greatly potentiated Xyl-induced hypertension for more than 30 min. The results suggested that Xyl-induced cardiovascular effects are similar to Xyn that mediated by alpha 2-adrenoreceptor. %U http://www.chinaphar.com/article/view/5586 %V 10 %N 5 %P 410-414 %@ 1745-7254