Stimulation test

Historically the only melanocortin peptide to be used clinically is the parent hormone from which all these peptides are derived from namely ACTH (see above). It has also been used in the treatment infantile spasms for epilepsy, where it is administered as an intramuscular injection only over a 2-12 weeks period. Obvious side effects include weight gain, puffy face, high blood pressure and an increased risk of infection and should never be administered to patients with diabetics, renal or heart failure. ACTH is also used as a stimulation test to measure adrenal cortex activity, i.e. production of cortisol and is used to ascertain whether someone has Addison s disease. 

The interesting properties of sulfosuccinates for inclusion in toiletry products stimulated testing of skin mildness for different types of sulfosuccinates. 

Check a pre-ACTH stimulation test cortisol level at 30, 60, and possibly 90 min post-ACTH administration... 

The unstimulated serum cortisol and rapid ACTH stimulation tests are useful in the diagnosis of adrenal crisis (Table 42-2). The insulin tolerance test is contraindicated owing to preexisting hypoglycemia. The metyrapone test is also contraindicated because metyrapone inhibits cortisol production. 

CRH stimulation test Response Rare response Decreased or no response No response No response... 

The patient will exhibit a peak GH level of less than 5 ng/mL (5 mcg/L) following a GH stimulation test. 

Stress-induced adrenal insufficiency complicates 9% to 24% of septic patients and is associated with increased mortality. Adrenal-insuffident patients are identified by a adrenocorticotropic hormone (ACTH) stimulation test. Patients are given 250 meg ACTH and a cortisol level is checked within 30 to 60 minutes. Responders are defined as a greater than 9-mcg/dL increase in cortisol and non-responders as a less than 9-mcg/dL increase in cortisol. Septic shock patients refractory to resuscitation and vasopressors, and with adrenal insufifidency (non-responders to the ACTH test) should be administered intravenous hydrocortisone 200 to 300 mg per day in three divided doses for 7 days.24,44... 

More specific laboratory tests are used to diagnose secondary hypertension. These include plasma norepinephrine and urinary metanephrine levels for pheochromocytoma, plasma and urinary aldosterone levels for primary aldosteronism, and plasma renin activity, captopril stimulation test, renal vein renins, and renal artery angiography for renovascular disease. 

Other tests that can help determine the etiology include the high-dose dexamethasone suppression test, plasma ACTH test, metyrapone stimulation test, corticotropin-releasing hormone stimulation test or inferior petrosal sinus sampling. 

The short cosyntropin-stimulation test can be used to assess patients with suspected hypocortisolism. An increase to a cortisol level >18 mcg/dL (500 mmol/L) rules out adrenal insufficiency. 

Patients with Addison s disease have an abnormal response to the short cosyntropin-stimulation test. Plasma ACTH levels are usually 400 to 2,000 pg/mL in primary insufficiency versus normal to low (0 to 50 pg/mL) in secondary insufficiency. A normal cosyntropin-stimulation test does not rule out secondary adrenal insufficiency. 

Other tests include the insulin hypoglycemia test, the metyrapone test, and the corticotrophin-releasing hormone stimulation test. 

The potencies of isomeric 2-acyloxy-2-phenylquinolizidines (which likewise differ in the orientation of phenyl with respect to the rest of the molecule) were also found to be alike in an electric stimulation test [284], but significant activity differences were seen in mice when a tail-flick procedure was used (see LXXXV) [285]... 

Currently there are few methods for specific investigation of immunotoxic effects, which are regarded as sufficiently validated for routine use (EC 2003). The plaque forming assay or the equivalent using the ELISA method (Enzyme-linked Immunosorbent Assay) are recommended to identify altered T-cell-dependent humoral responses. Of particular value for hazard assessment are the so-called host resistance models, in which the clinical relevance of immunotoxicity can be evaluated. Other methods may also be of value to provide information on the mode of immunotoxic action, e.g., mitogen stimulation tests and leucocyte phenotyping. However, further work is needed on standardization and validation of these test methods. 

Monitoring Baseline and periodic caloric stimulation tests and audiometric tests are adyisable with extended streptomycin therapy. Tinnitus, roaring noises, or a sense of fullness in the ears indicates need for audiometric examination, termination of streptomycin therapy, or both. 

The CRF Challenge Test and ACTH Stimulation Test in PTSD. 389... 

Kosten TR, Wahby V, Giller E, Mason J (1990) The dexamethasone suppression test and thyrotropin-releasing hormone stimulation test in posttraumatic stress disorder. Biol Psychiatry 28 657-664... 

Krishucm KRR, Rayasam K, Reed D, Smith M, ChapeU P, Saunders WB, Ritchie JC, Carroll BJ, Nemeroff CB (1993) The corticotropin releasing factor stimulation test in patients with major depression relationship to dexamethasone suppression test results. Depression 1 133-136... 

Indirect evidence for hypothalamic CRF hypersecretion comes from CRF stimulation test studies in which patients with depression typically show blunted ACTH responses, likely reflecting, in part, down-regulation of pituitary CRF receptors. These findings are similar to the reduction of pituitary CRF receptors in maternally... 

Amsterdam JD, Maishn G, Winokur A, et al Pituitary and adrenocortical responses to ovine corticotropin-releasing hormone stimulation test. Arch Gen Psychiatry 44 775-781, 1987c... 

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