Production of Steroids byin VitroSuperfusion of Endocrine Tissue. III. Corticosterone Output from Rat Adrenals Stimulated by Adrenocorticotropin or Cyclic 3′,5′-Adenosine Monophosphate and the Inhibitory Effect of Cycloheximide

Stimulation of Carp Interrenal Function by Adrenocorticotrophin

“…Similar experiments performed in the adrenals of the rat (Schulster, Tait, Tait & Mrotek, 1970) and rabbit (Saffran et al 1967) yielded a longer time-interval (5 h) for such a decrease in release of corticosterone. The high initial rate of corticosteroid release is attributed to the effect of increased endogenous ACTH resulting from the stress of handling the animals before death (Saffran et al 1967).…”

Gastric Effects of Cycloheximide

“…The effect of cycloheximide on acid secretion seems analogous to the almost immediate inhibition by cycloheximide of the rapid, adrenocorticotrophinevoked secretion of corticosterone from the adrenal [7,18], It was postulated that the rapid inhibitory effect of cycloheximide on the adrenal cortex was exerted at the stage of adrenocorticotrophin-elicited protein synthesis repre sented by translation of stable mRNA [7] and a similar effect may explain the inhibitory effect of cycloheximide on secretagogue-evoked acid secretion from the stomach. The time scale of the stimulation and inhibition of gastric acid secretion would permit a role for the induction of protein synthesis in the process of acid formation, since the gastric acid response, which may start within 2-3 min of secretagogue administration, takes from about 10 to 50 min to reach maximal levels, depending on the stimulant, while the syn thesis of proteins from amino acids may be much more rapid.…”

“…Other actions of cycloheximide which are direct and not dependent on changes secondary to alterations in protein synthesis, have been sought, but not found, although cycloheximide has been used in the study of cellular metabolism for many years. Thus, Schulster et al [18] showed that the inhibitory effects of cycloheximide were at least partially reversible, so that permanent tissue damage was not produced, while Kirk [II] noted that cycloheximide had no effect on energy metabolism. Hence, it seems permis sible to postulate that protein synthesis is involved in the secretion of acid by the stomach.…”

“…D intzis [6] concluded that rabbit reticulocyte ribosomes add amino acids, when forming haemoglobin molecules, at a rate of 'approximately two amino acids per second'. Cycloheximide is known to begin to inhibit protein synthesis within a few minutes of administration [7,18].…”

Action of adrenocorticotrophin on a preparation of isolated cells from rat adrenals

“…Decapsulated glands were quartered and digested with collagenase (Sigma type I; 5mg/ml) in KrebsRinger bicarbonate buffer, pH 7.4 containing glucose (0.2%) and albumin (3%, w/v (Schulster, Tait, Tait & Mrotek, 1970).…”