ACTH Secretion and Tissue Content

Several methods have been described, starting with radio-immunoassay procedures (Rees 1971, Kao 1979, Krieger 1975), and proceeding to immunoradiometric methods (Hodgkinson 1984, White 1987, Zahradnik 1989, Raff 1989, Gibson 1989, Fukata 1989). 

For practical application, a method should be selected that can be applied to unextracted serum, provided that ACTH degradation is prevented by adding an enzyme inhibitor at the time of blood collection. 

CRITICAL ASSESSMENT OF THE METHOD A very critical item has been a tendency of ACTH to fluctuate widely and rapidly under conditions of stress (Meeran 1989, Lambert 1985, Goverde 1989). This is especially a problem in studies with dogs, where the experiments need to be performed under stress-free conditions and even then there will be the difficulty of rapidly fluctuating concentrations. 

Fukata J (1989) Two-site immunoradiometric assay for adreno-corticotrophin a cautionary study about the reactivity to its precursor molecules. Endocrinol Jpn 36 155-61 Ganong WF (1974) ACTH and the regulation of adrenocorticol secretion. N Engl J Med 290 1006 Genazzani AR (1975) Immunoreactive ACTH and cortisol plasma levels during pregnancy. Detection and partial purification of corticotrophin-like placental hormone the human chorionic corticotrophin (HCC). din Endocrinol (Oxf) 4 1-14 

Gibson S (1989) Advantages of IRMA over RIA in the measurement of ACTH. Ann Clin Biochem 26 500-7 Goverde HJ (1989) The bioactivity of immunoreactive adreno-corticotrophin in human blood is dependent on the secretory state of the pituitary gland. Clin Endocrinol (Oxf) 31 255-65 

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