Challenges in Modelling Hypoglycaemia-Associated Autonomic Failure: A Review of Human and Animal Studies

Table 2

Summary of procedures used to reproduce the HAAF phenomenon in rodents.

	Species	Route of administration	Insulin dose used to induce antecedent hypoglycaemia	Insulin dose used to induce subsequent hypoglycaemia	Fasting condition	Blood glucose measurement (method of sampling and assay)	Depth and duration of antecedent hypoglycaemia	Number of antecedent hypoglycaemic episodes	Plasma adrenaline in response to antecedent/subsequent hypoglycaemia (in pg/mL) and method of assay
Nondiabetic rats	Sprague-Dawley rats [28–41]; Wistar rats [42–44]	s.c [28, 29, 32]; i.v [35, 36, 39, 40, 42–44]; s.c and i.v [37]; i.p and i.v [30, 31, 33, 34, 41]	1–3 U/kg [28, 30, 32, 37, 38, 40, 42, 43]; 5–10 U/kg [31, 33, 34, 39, 41, 44]; 12 U/kg [29]; 4 U/kg and additional 0.5–1 U/kg [35]; 10 U/kg and 6–8 U/kg [36]	1–3 U/kg [28, 40, 42]; 5–10 U/kg [28, 35, 36, 43, 44]; 12 U/kg [29]; 20–50 mU/kg/min [30, 31, 33, 34, 38, 41]; 0.75 U/kg followed by 1.8 U/kg/hr [37]; 0.75 U/kg 3 times at 5 min interval [35]	Fasted overnight [33]; Nonfasted [28, 29, 31, 36, 37, 39–44]; Overnight prior to subsequent hypoglycaemia [30, 34, 35, 38]; Fasted for four hours prior to subsequent hypoglycaemia [32]	Tail [32, 34, 40]; Systemic [28, 30, 35, 39, 41–44]; Tail/systemic [31, 36–38]; Trunk [29]; Glucometer [30, 32, 36, 40]; Glucose oxidase method [28, 29, 33–39, 42, 43]; Modified Trinder’s reaction assay [44]	1.4–1.9 mmol/L [28, 31, 35, 37, 39, 42, 43]; 2–3.2 mmol/L [30, 32–34, 36, 38, 40]; 1-2 hrs [28, 31, 32, 35, 37, 39, 40, 42–44]; 3 hrs [30, 33, 34, 36, 38, 41]; Depth and duration not given [29]	1/day for 1 day [33, 35, 39]; 1/day for 2 days [37]; 1/day for 3-4 days [29, 31, 32, 34, 36, 40, 41]; 2/day for 1 day [28, 42–44]; 2/day for 2 days and 1/day on third day [30, 38]	450–1000/175–460;  –0.01 [28, 32, 36]; 1000–3000/740–1500;  –0.01 [30, 37–40, 43]; 3000–5000/1500–2400;  –0.01 [31, 33–35, 41, 42]; 1600/1000;    [44]; 3800/3250; [29]; HPLC [31–35, 37, 39–41]; RIA [28, 42–44]; ELISA [29, 30, 36, 38]
Diabetic rats	Streptozotocin-induced diabetic Sprague-Dawley rats [45, 46]	i.p [45]; s.c and i.v [46]	6–10 U/kg [45]; 2 U/kg [46]	6–10 U/kg [45]; 10 mU/kg/min [46]	Nonfasted [45]; Overnight prior to subsequent hypoglycaemia [46]	Not given [45]; Systemic [46]; Glucose oxidase method [45, 46]	2.8 mmol/L [45]; 2.2 mmol/L [46]; 3 hrs [45]; 1 hr [46]	1/day for 3 days [45]; 2/day for 3 days and 1/day on 4th day [46]	3010/890; [45]; 5076/5076; [46]; HPLC [45]; RIA [46]
Nondiabetic mice	C57BL/6 [47, 48]	i.p [48]; i.v [47]	2.5 U/kg [48]; 20 mU/kg/min [47]	2.5 U/kg [48]; 20 mU/kg/min [47]	3 hours prior to injections on all days [48]; 6 hours prior to each episode [47]	Tail [48]; Systemic [47]; Glucometer [47, 48]	2.2 mmol/L [48]; 3.8 mmol/L [47]; 3 hrs [48]; 2 hrs [47]	1/day for 4 days [48]; 1/day for 1 day [47]	14000/15000; [48]; 220/120; [47]; HPLC [47]; ELISA [48]

RIA: radioimmunoassay; HPLC: high-performance liquid chromatography; ELISA: enzyme linked immunosorbent assay.