Comparison of the antagonistic effects of yohimbine and 4-aminopyridine in dogs under xylazine-ketamine anesthesia
Takase, K.; Hikasa, Y.; Irie, Y.; Ogasawara, S.
Kitasato Archives of Experimental Medicine 60(3): 87-94
1987
ISSN/ISBN: 0023-1924 PMID: 2838682 Document Number: 291751
A mixture of xylazine and ketamine at 2 and 10 mg/kg, respectively, was given i.m. to 48 adult dogs weighing 15-30 kg. Ten received i.v. a mixture of 0.05 mg/kg yohimbine and 0.3 mg/kg 4-aminopyridine (4-AP); 3 groups of 6 received one of these drugs alone or saline. The 5 recovery criteria were significantly shortened by the treatments, the least effective being 4-AP. Mild, transient muscle rigidity was seen in 3 having the mixture and in 4 having yohimbine alone. Yohimbine and, to a lesser extent, 4-AP prevented hypothermia. All treatments antagonized the inhibition of respiration induced by anaesthesia. The mixture and yohimbine alone caused a higher heart rate and, in a further study with 4 groups of 5 dogs, a transient fall in blood pressure. It was concluded that a mixture of yohimbine and 4-AP and yohimbine alone effectively antagonized xylazine-ketamine anaesthesia.