Propofol relieves the subcutaneous chloroquine-induced pruritus in rats via TRPV1 and CB1 receptors of spinal cord / 中国临床药理学与治疗学

ABSTRACT

AIM: To explore the possible mechanism of propofol in alleviating pruritus induced by subcutaneous injection of chloroquine in rats. METHODS: The pruritus model of chloroquine in SD rats was established and the administration time was determined. 18 rats with successful pruritus model induced by subcutaneous injection of chloroquine were randomly divided into NS group, I group and P group. Normal saline 80 μL/kg, fat emulsion 80 μL/kg and propofol 0.8 mg/kg were injected through internal jugular vein catheter 5 minutes after subcutaneous injection of chloroquine. Another 6 rats were randomly selected as group C, and the same volume of normal saline as the other 3 groups was injected subcutaneously in the back of the neck and through the internal jugular vein catheter. The rats were killed 16 minutes after the corresponding drugs were injected into the internal jugular vein. The expressions of TRPV1 and CB1 receptors in the spinal cord were detected by Western blot. RESULTS: Compared with NS group and I group, the expression level of TRPV1 receptor in the spinal cord of P group rats was significantly increased (P<0.01), while there was no statistically significant difference between C group, NS group, and I group; The expression level of CB1 receptor was significantly higher than that of group C, NS, and I (P<0.05), while there was no statistically significant difference between group C, NS, and I. CONCLUSION: Propofol can significantly alleviate pruritus caused by subcutaneous injection of chloroquine in rats, which may exert an antipruritic effect by increasing the expression of TRPV1 and CB1 receptors in the spinal cord of rats.