Corticosteroids in plasma and cells of adrenal venous blood

Abstract

Investigations by several authors appeared to show that no appreciable amounts of corticosteroids are present in the cell fraction of adrenal venous blood (Bibile, 1953) or in peripheral human blood (Eik-Nes, Nelson & Samuels, 1953;Migeon, Sandberg, Decker, Smith, Paul & Samuels, 1956;Bush, 1957). This view has been generally accepted and as a result most of the estimates of the secretory capacity of the adrenal cortex have been carried out by studying the steroid content of the plasma alone. There are, however, hints in the literature that corticosteroids might become associated with the blood cells (Peterson, Wyngaarden, Guerra, Brodie & Bunim, 1955;Bush, 1957).Studies on the secretion rate of aldosterone are made difficult by the very low concentrations of this steroid in adrenal venous plasma. It seemed, therefore, desirable to examine the possibility that some aldosterone was associated with the cells. A sample of adrenal venous blood was divided into two equal portions. One of these was centrifuged and the plasma and cells were extracted separately. The other portion was extracted as whole blood. The experiment showed that some aldosterone was, in fact, extracted from the cells, so that by using plasma alone a valuable source of aldosterone was wasted. It also showed that the estimate of aldosterone in the whole-blood sample was approximately three times as large as the sum of the estimates of aldosterone in the separated plasma and cell fractions of the same blood. This suggested that the method of extraction used broke down when applied to the closely packed cell fraction. These observations have been followed up and the experiments have been extended to include estimations of corticosterone and cortisol. METHODS Operative procedure8Mongrel dogs were anaesthetized with ether followed by chloralose (70 mg/kg i.v.). The left adrenolumbar vein was exposed by an abdominal mid-line incision and cannulated

Humoral Stimulation of Adrenal Cortical Secretion*

“…It follows, therefore, that if blood flow is 800 ml per hour and 30 ml of adrenal venous plasma is extracted [twice as much as, for example, that usually used in the method of Reich (35)], aldosterone cannot be detected visually until the adrenal secretion rate is approximately (600 X 0.2) /30 = 4 ltg per hour. This calculation assumes that the recovery of aldosterone through extraction and separation from other steroids is 100 per cent and does not take into account aldosterone associated with the discarded red blood cells (36)(37)(38)(39). Chromatography adequate to purify aldosterone may result in the loss of up to 30 to 50 per cent (29,34,38,40).…”

“…This calculation assumes that the recovery of aldosterone through extraction and separation from other steroids is 100 per cent and does not take into account aldosterone associated with the discarded red blood cells (36)(37)(38)(39). Chromatography adequate to purify aldosterone may result in the loss of up to 30 to 50 per cent (29,34,38,40). It seems probable, therefore, that even if plasma flow rate is 300 to 400 ml per hour aldosterone will not be detected visually until adrenal secretion rate approaches 4 jtg per hour.…”

Adrenal secretion rates and adrenal tissue concentrations of pregnenolone, progesterone, 11βOH‐androstenedione and some other steroids in young pigs and dogs

“…The extracts were freed from fats and phospholipids (see Holzbauer, 1964). As for the estimation of glucocorticoids and aldosterone (Holzbauer & Vogt, 1961), the use of whole blood instead of plasma was desirable also for other steroids. In a study of the distribution of progesterone between plasma and blood cells in rat adrenal venous blood only one half of the total amount of progesterone present was obtained when the plasma fraction alone was extracted.…”

Evidence for the presence of 16α‐hydroxypregn‐4‐ene‐3,20‐dione in adrenal venous blood of young pigs

“…The second part of the combined sample was evaporated to dryness, acetylated (Holzbauer & Vogt, 1961) and chromatographed in the B3 system for 3-hr. Authentic 16ac-OH-progesterone (20 ,tg) and compound S (20 ,tg) were treated in the same way.…”