Due to the unique physiological characteristics of ruminants, the process of their clinical anesthesia includes numerous adverse factors. In this study, we investigated the effects of xylazine anesthesia on the goat NO/cGMP signal transduction system. We explored changes of NOS activity, NO content, and cGMP concentrations in different encephalic regions of goats after xylazine anesthesia. Fifteen goats were divided into five groups: saline control group, induction period, anesthesia period, recovery period 1, and recovery period 2, respectively. Cerebrum, cerebellum, brainstem, hippocampus, and thalamus were collected. The results showed that the contents of NOS, NO, and cGMP in cerebrum, cerebellum, hippocampus, thalamus, and brainstem had significantly decreased during the period of anesthesia. The activity of NOS decreased by 51.0, 39.1, 39.7, 41.1 and 25.4%, respectively (P<0.01), the content of NO decreased by 39.0, 31.1, 17.1, 21.7 and 27.4%, respectively (P<0.01), and the concentrations of cGMP decreased by 56.4, 43.4, 40.9, 59.2 and 40.0% (P<0.01). The recovery period returned to normal level. The xylazine effect may be associated with the inhibition of the NO/cGMP signal transduction pathway in each encephalic region of goats.

Key words: cGMP, goat, NO, NOS, xylazine