In hypoadrenal subjects, a further sample at 12 to 16 hours is indicated.

injection of 1 mg Synacthen Depot, generally recommended to be given at about 10 a.m. (1971) proposed as a test of adrenal function that plasma-cortisol be estimated before and 4 to 6 hours after an i.m. reasonably inferring that, except perhaps in states of extreme collapse, little advantage is to be gained in speed of response by giving cosyntropin (short acting) i.v. (1969) found that the speed of response in the first 20 to 30 minutes is also virtually the same after cosyntropin i.v. infusion, which is frequently unpleasant for both patient and clinician. injection of 1 mg of depot cosyntropin in a group of patients with varying degrees of adrenocortical insufficiency secondary to corticosteroid therapy suggesting its use to test for adrenocortical insufficiency without recourse of i.v. (1969) found that there was no significant difference in plasma 11-hydroxycorticosteroid response over 4 hours after a cosyntropin infusion or a single i.m. In addition, there is also hypertrophy and hyperplasia of the adrenal cortex, in contrast to the effect of the exogenous corticoids.ДЄdrenal Function Test: The assessment of adrenocortical function based on its response to exogenous ACTH is well established. The long-term administration produces the same effects as those produced by cortisone, cortisol and their synthetic analogues. Therefore, therapy may be maintained with less frequent administration. The complex results in a product whose absorption in man is effected over a longer period of time as compared to corticotropin. Synacthen Depot, a long-acting synthetic b1-24-corticotropin, exhibits the same activity as natural ACTH with regard to all its biological activities. It also has some degree of melanotropic activity and lipolytic effect. In addition to controlling corticosteroid secretion, ACTH also increases the synthesis and release of the other adrenal steroids, namely aldosterone and the adrenal androgens. In its absence, adrenal blood flow is diminished, adrenal atrophy invariably ensues and cortisol secretion is markedly reduced. The most important physiological effects of ACTH involve the adrenal cortex and include the maintenance of adrenal weight and the control of adrenal corticosteroid synthesis and release. In contrast, the N terminal 24 amino-acid sequence is common to all species and is relatively non-antigenic, and it is only these amino-acids which are involved in its biological activities.: The sequence of amino-acid occupying positions 25 to 33 varies among species and it is this part of the molecule which is most antigenic when ACTH of foreign origin is administered to man. Natural adrenocorticotropin is a straight-chain polypeptide containing 39 amino acids which, by convention, are numbered from the N terminal end of the molecule.

Synacthen atc4