Intraperitoneal(lP) administration of anesthesia is commonly used for laboratory animal experiment including islet isolation using abdominal organ. However, the direct effects of anesthetics towards organs of abdom?inal cavity such as pancreas have been neglected. To evaluate the direct effects of anesthetic agents to the pancreas when isolating pancreatic islets, we compared the islet function and recovery yield from the rats that were anesthe?tized using IP and intramuscular(IM) routes. Lewis was anesthetized using the combination of zoletil and xyla?zine(Z/X). These drugs were injected through 1M or IP route. To shot 1M drugs, we have invented a specially designed restrainer. Glucose challenging test was performed with each group of prepared islets within 30 minutes after isolation procedure. Yield of isolated islets by 1M route was significantly improved(1M: 1136±226 ea, IP: 511±154 ea). Function of fresh islet with 1M route was better kept than oflP, which was expressed by stimulation index. For rodent islet isolation, 1M route for anesthesia is simpler and safe way compared with IP route. It is sug?gested that 1M route is versatile in laboratory animal experiments.