Rapid insulin sensitivity test (RIST)

Abstract

A rapid insulin sensitivity test (RIST) was recently introduced to assess insulin action in vivo (H. Xie, L. Zhu, Y.L. Zhang, D.J. Legare, and W.W. Lautt. J. Pharmacol. Toxicol. Methods, 35: 77-82. 1996). This technical report describes the current recommended standard operating procedure for the use of the RIST in rats based upon additional experience with approximately 100 tests. We describe the manufacture and use of an arterial-venous shunt that allows rapid multiple arterial samples and intravenous administration of drugs. The RIST procedure involves determination of a stable arterial glucose baseline to define the ideal euglycemic level to be maintained following a 5-min infusion of insulin, with the RIST index being the amount of glucose required to be infused to maintain euglycemia over the test period. Insulin administration by a 5-min infusion is preferable to a 30-s bolus administration. No significant difference was determined between the use of Toronto pork-beef or human insulin. Four consecutive RISTs were carried out in the same animal over 4-5 h with no tendency for change with time. The RIST index is sufficiently sensitive and reproducible to permit establishment of insulin dose-response curves and interference of insulin action by elimination of hepatic parasympathetic nerves, using atropine. This technical report provides the current recommended standard operating procedure for the RIST.

Elevation of Global O-GlcNAc in Rodents Using a Selective O-GlcNAcase Inhibitor Does Not Cause Insulin Resistance or Perturb Glucohomeostasis

“…The tail vein was then catheterized and sodium pentobarbital was delivered at a constant rate of 11 mg·kg -1 ·min -1 (in saline containing 20 U/ml heparin) for the remainder of the experiment in a total volume of 2 ml. While unconscious, a catheter was inserted in the femoral artery and then looped back into the femoral vein to create a blood sampling loop that minimized blood loss (Lautt et al., 1998). For 2 hr, insulin (2.5 ml in total) (Eli Lilly) and a 50% solution of glucose were delivered to the animal via the tail vein catheter.…”

Obesity as an Early Symptom of the AMIS Syndrome

“…The dynamic action of insulin and HISS can be determined using the insulin tolerance test [ 24 ]; however, the ensuing hypoglycemia limits its use. To avoid the hypoglycemia, and to detect the dynamic response to pulses of insulin, the Rapid Insulin Sensitivity Test (RIST) was developed and has been used in cats [ 25 ], anesthetized [ 2 ] or conscious [ 12 ] rats, mice [ 26 ] rabbits [ 27 ] and humans [ 14 ]. The RIST is a rapidly sampled and adjusted euglycemic clamp that provides reproducible test scores up to 4 consecutive times in anesthetized rats [ 2 ].…”

“…MIS was reported in 1998 [ 1 , 2 ] and an overview of the working HISS hypothesis was first reviewed in 1999 [ 3 ]. To our knowledge, only the Lautt lab in Canada, the Macedo team in Portugal, and Szilvassy’s group in Hungary have studied meal-induced insulin sensitization (MIS).…”

Hemorrhage Results in Hepatic Insulin-Sensitizing Substance-Dependent Insulin Resistance Mediated by Somatostatin in Rats

“…Temperature was monitored by a rectal thermometer and kept constant at 37.5 ± 0.5°C by a heated surgical table and an overhead lamp. The right femoral artery and vein were cannulated with catheters (polyethylene tubing PE60) that were connected by silicon tubing [Masterflex – silicon tubing (Platinum) L/S 14], allowing blood to flow uninterrupted from the artery to the vein [14]. Blood samples were taken by puncturing through the silicon tubing in the shunt.…”

“…The amount of glucose infused over the RIST (mg glucose/kg of body weight) is known as the RIST index. The RIST is capable of measuring both HISS-dependent and HISS-independent insulin action [14]. …”