Fentanyl inhibits glucose-stimulated insulin release from β-cells in rat pancreatic islets

Table 1 The glucose-stimulated insulin release (μIU) in response to fentanyl with different concentrations of naloxone (mean ± SD, n = 12 )

	Fentanyl alone		Fentanyl + 0.1μg/mL naloxone		Fentanyl + 1μg/mL naloxone
	Low glucose	High glucose	Low glucose	High glucose	Low glucose	High glucose
Control (0 ng/mL)	62.33 ± 9.67	125.5 ± 22.04	62.33 ± 9.67	125.5 ± 22.04	62.33 ± 9.67	125.5 ± 22.04
I (0.3 ng/mL)	54.75 ± 5.93a	118.17 ± 16.81	54.33 ± 8.99	110.4 ± 15.69	61.5 ± 8.13	126.75 ± 16.48
II (3 ng/mL)	47.75 ± 8.47b	96.17 ± 14.17b	45.92 ± 7.63b	88.25 ± 11.22d	59.75 ± 8.42	118.33 ± 21.09
III (30 ng/mL)	39.67 ± 6.18b	75.17 ± 13.57b	36.33 ± 5.79b	68.67 ± 11.99d	61.08 ± 8.07	126.0 ± 15.54
Naloxone			61.67 ± 9.16	120.3 ± 18.04	60.67 ± 9.15	123.0 ± 20.89

^aP < 0.05,

^bP < 0.01 vs control group (Mann-Whitney U test);

^dP < 0.01 vs control group (LSD test). Low- and high-glucose-stimulated insulin release in the 3 and 30 ng/mL fentanyl groups was significantly lower than in the control group (P < 0.01), and was lowest with 30 ng/mL fentanyl (P < 0.01). After adding 0.1 μg/mL naloxone, insulin secretion in the 3 and 30 ng/mL fentanyl groups remained significantly lower than the control group (P < 0.01) and was lowest with 30 ng/mL fentanyl (P < 0.01).

Table 2 Stimulation index at different concentrations of fentanyl and naloxone (mean ± SD, n = 12)

	Fentanyl	Fentanyl + 0.1μg/mL naloxone	Fentanyl + 1μg/mL naloxone
Control (0 ng/mL)	2.01 ± 0.21	2.02 ± 0.21	2.02 ± 0.21
I (0.3 ng/mL)	2.17 ± 0.36	2.07 ± 0.35	2.08 ± 0.26
II (3 ng/mL)	2.04 ± 0.26	1.95 ± 0.23	1.99 ± 0.34
III (30 ng/mL)	1.89 ± 0.16	1.89 ± 0.19	2.08 ± 0.27
Naloxone		1.97 ± 0.29	2.04 ± 0.28