<prompt> Insulin stress test assay estimates -Diabetes mellitusGrowth hormoneGlucagon assayCatecholaines  <response>: An insulin tolerance test ITT is a medical diagnostic procedure during which insulin is injected into a patients vein, after which blood glucose is measured at regular intervals. Normally, both coisol and GH serve as counterregulatory hormones, opposing the action of insulin, i.e. acting against the hypoglycemia . When used to assess insulin sensitivity, a standard dose of insulin is administered, and blood glucose is monitored with frequent sampling; the plasma glucose disappearance rate KITT indicates the degree of whole-body insulin sensitivity . Ref - pubmed.com 