diff --git a/src/datasource-zabbix/query.controller.js b/src/datasource-zabbix/query.controller.js
index 48465a5..6d295a0 100644
--- a/src/datasource-zabbix/query.controller.js
+++ b/src/datasource-zabbix/query.controller.js
@@ -282,10 +282,9 @@ export class ZabbixQueryController extends QueryCtrl {
    * Update list of IT services
    */
   updateITServiceList() {
-    var self = this;
-    this.datasource.zabbixAPI.getITService().then(function (iteservices) {
-      self.itserviceList = [];
-      self.itserviceList = self.itserviceList.concat(iteservices);
+    this.zabbix.getITService().then((iteservices) => {
+      this.itserviceList = [];
+      this.itserviceList = this.itserviceList.concat(iteservices);
     });
   }
 
diff --git a/src/datasource-zabbix/zabbix.js b/src/datasource-zabbix/zabbix.js
index fd995b0..254d79b 100644
--- a/src/datasource-zabbix/zabbix.js
+++ b/src/datasource-zabbix/zabbix.js
@@ -30,6 +30,7 @@ function ZabbixFactory(zabbixAPIService, ZabbixCachingProxy) {
       this.getTrend = this.zabbixAPI.getTrend.bind(this.zabbixAPI);
       this.getEvents = this.zabbixAPI.getEvents.bind(this.zabbixAPI);
       this.getAcknowledges = this.zabbixAPI.getAcknowledges.bind(this.zabbixAPI);
+      this.getITService = this.zabbixAPI.getITService.bind(this.zabbixAPI);
       this.getSLA = this.zabbixAPI.getSLA.bind(this.zabbixAPI);
       this.getVersion = this.zabbixAPI.getVersion.bind(this.zabbixAPI);
       this.login = this.zabbixAPI.login.bind(this.zabbixAPI);