[Experimental studies on a plant extract from Echinacea purpurea Moench as a nonspecific irritant. With special reference to the effect on the adrenal cortex].
Explore the source record for details and available documents.
SEARCH · Search PubMed
Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
Explore the source record for details and available documents.
Endogenous digoxin-like immunoreactive factors (DLIF) are present in serum and tissues of humans and animals. To date, a tissue source for these factors has not been rigorously defined nor have these factors been isolated to identifiable homogeneity. In this study, we define the distribution of DLIF in mammalian tissues, demonstrate the adrenal cortex to be the principal source of this factor in bovine, and isolate DLIF to chromatographic homogeneity using high performance liquid chromatography (HPLC). DLIF concentrations in tissue extracts from rats measured as follows: adrenal glands, 44.3; serum, 6.3; liver, 5.2; kidney, 1.2; heart, brain, or lungs, less than 1.4 ng of digoxin-equivalent per g of protein. Human tissues showed similar results. In dogs, the ratio of the DLIF concentration in lumbar vein serum to that in infrarenal inferior vena cava serum was 3.3 +/- 0.4 (mean +/- S.E., n = 4). Bovine adrenal cortex contained 7 times more DLIF per g of tissue than the adrenal medulla. 70 +/- 4% (n = 7) of the total bovine cortical DLIF activity (6,159 pg of digoxin-equivalent) applied to a reverse phase HPLC column eluted as one definitive fraction. 60% of the digoxin-like immunoreactivity extracted from bovine serum also co-eluted with DLIF from adrenal. None of the 14 steroid molecules or 7 cardiac glycoside congeners co-eluted with the major DLIF activity. Our data indicate that 947 pmol of DLIF is equivalent to 1 pmol of digoxin-equivalent immunoreactivity. Preliminary mass spectral analysis suggests that purified DLIF has a molecular mass of 780 daltons comprised of one 390-dalton aglycone component plus several sugar moieties. This study establishes a definitive link between DLIF in serum and the adrenal cortex as a source tissue. We also demonstrate a method for purifying DLIF to chromatographic homogeneity with an extraction capacity of 1.2 nmol of DLIF per g of adrenal cortex.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
The study aimed to find out the effect of sulfonamide combined with Trimetaprim-Biseptol 480 on the adrenal cortex in post-operative shock after removal of SPIGELian lobe (lobectomy of the lobus caudatus and unilaterally of one kidney with its suprarenal gland. The study was performed on a material of white rats which were post-operatively administered Biseptol 480 in doses 5 times bigger than those given to men. It was attempted to determine histochemically the intensity of the adrenal cortex' function by testing the number of lipid droplets, activity of the main enzyme of steroidogenesis (beta-hydroxy steroid dehydrogenase) and the level of alpha-ketols (as the final stage of steroidogenesis). Pathomorphologic examinations were also performe. On the basis of the present study's results, it was observed that - in the case of liver-lobectomy - the zona fasciculata and zona reticularis are functionally stimulated but the zona glomerulosa becomes insufficient. In the case of nephrectomy plus suprarenal gland's removal, all the adrenal cortex becomes insufficient. Administration of Biseptol in the 1st case contributed to hormonal inactivation of the zone glomerulosa cells, but in the 2nd case, it caused an increased activity of steroid dehydrogenase and an increase of the alpha-ketol level in the zona fasciculata.
Autoimmune Addison's disease and premature ovarian failure are characterized by the presence of organ-specific autoantibodies. The main adrenal and gonadal autoantigens have been identified and cloned, and the relationship between the autoantibodies detected by immunofluorescence techniques and those detected by the new assays using recombinant autoantigens needed to be investigated. We studied 165 patients with Addison's disease: 143 patients had different forms of autoimmune Addison's disease (13 with idiopathic premature ovarian failure) and 22 had nonautoimmune Addison's disease. Adrenal-cortex autoantibodies and steroid-producing cell autoantibodies were measured by the immunofluorescence techniques. Autoantibodies to steroid 21-hydroxylase, 17alpha-hydroxylase, and P450 side chain cleavage enzyme were measured by immunoprecipitation assay using 35S-labeled recombinant proteins. Adrenal-cortex autoantibodies and autoantibodies to 21-hydroxylase were found in 81% of the patients with autoimmune Addison's disease. None of the patients with nonautoimmune Addison's disease had adrenal-cortex autoantibodies or autoantibodies to 21-hydroxylase. A high association between these two markers in patients with different forms of autoimmune Addison's disease and in those with short- or long-standing disease was found. Steroid-producing cells autoantibodies were found in 26% of the patients with autoimmune Addison's disease, and autoantibodies to 17alpha-hydroxylase and/or P450 side chain cleavage enzyme in 36% of the patients. Steroid-producing cells autoantibodies were found in 11/13 (85%) of patients with idiopathic premature ovarian failure associated with autoimmune Addison's disease, and autoantibodies to 17alpha-hydroxylase and/or P450 side chain cleavage were found 12/13 (92%) of patients; the only case negative for all these three markers suffered from Turner's syndrome. Provided that a high standard of immunofluorescence technique is maintained, measurement of adrenal cortex autoantibodies or steroid-producing cells autoantibodies by either immunofluorescence or immunoprecipitation assay is essentially equivalent.
Evidence is presented demonstrating the presence of a high affinity (Ka10(8)M-1), limited capacity (3-4 pmoles/mg protein) estradiol binder in the soluble fraction of the Bovine, Rat and Human adrenal cortex. The binding appears specific to the estrogen structure whereas C19 and C21 steroids do not bind. Upon sucrose density gradient centrifugation, the estradiol binder sedimented at 9 S at low ionic strength and was shifted to 4.5 S in the presence of 0.5 M KCl. This demonstration of a receptor-like moiety for estradiol in the adrenal cortex lends biochemical support to previous observations suggesting that adrenal cortex functions may be modulated by a direct effect of gonadal steroid hormones.
The molecular mechanisms leading to adrenocortical tumorigenesis have been only partially elucidated so far. Because the pituitary hormone ACTH, via activation of the cAMP pathway, regulates both cell proliferation/differentiation and steroid synthesis in the adrenal cortex, in this study we focused on the cAMP-dependent transcription factors cAMP responsive element modulator (CREM) and cAMP responsive element binding protein (CREB). We studied CREM and CREB expression by RT-PCR in human normal adrenal cortex (n = 3), adrenocortical adenomas (n = 8), and carcinomas (n = 8). We found transcripts corresponding to the isoforms alpha, beta, gamma, and tau2 of the CREM gene in all of the normal adrenal tissues, in the adenomas, and in seven of eight carcinomas. On the other hand, mRNA for the inducible cAMP early repressor isoforms, which derive from an internal promoter of CREM gene, was detected in the normal adrenal and in seven of eight adenomas, but in only three of eight carcinomas. Similarly, CREB transcripts were readily detectable in all normal adrenals and adenomas, whereas they were not found in four of eight adrenal carcinomas. To further characterize the carcinomas, telomerase activity and the expression of the ACTH receptor gene were determined. Telomerase activity in the carcinomas resulted in levels significantly higher than in the adenomas, whereas the levels of ACTH receptor mRNA were lower in the carcinomas. No correlation was found in the carcinomas between the levels of the ACTH receptor transcript and the loss of expression of CREB/inducible cAMP early repressor, suggesting that this alteration is not secondary to an upstream disregulation at the receptor level. In conclusion, our results suggest that an alteration in cAMP signaling may be associated with malignancies of the adrenal cortex.
A cytochrome P-450 capable of producing aldosterone from 11-deoxycorticosterone was purified from the zona glomerulosa of rat adrenal cortex. The enzyme was present in the mitochondria of the zona glomerulosa obtained from sodium-depleted and potassium-repleted rats but scarcely detected in those from untreated rats. It was undetectable in the mitochondria of other zones of the adrenal cortex from both the treated and untreated rats. The cytochrome P-450 was distinguishable from cytochrome P-45011 beta purified from the zonae fasciculata-reticularis mitochondria of the same rats. Molecular weights of the former and the latter cytochromes P-450, as estimated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, were 49,500 and 51,500, respectively, and their amino acid sequences up to the 20th residue from the N terminus were different from each other at least in one position. The former catalyzed the multihydroxylation reactions of 11-deoxycorticosterone giving corticosterone, 18-hydroxydeoxycorticosterone, 18-hydroxycorticosterone, and a significant amount of aldosterone as products. On the other hand, the latter catalyzed only 11 beta- and 18-hydroxylation reactions of the same substrate to yield either corticosterone or 18-hydroxydeoxycorticosterone. Thus, at least two forms of cytochrome P-450, which catalyze the 11 beta- and 18-hydroxylations of deoxycorticosterone, exist in rat adrenal cortex, but aldosterone synthesis is catalyzed only by the one present in the zona glomerulosa mitochondria.
The adrenal cortex of 32 newborns and of 3 anencephalic monsters of 16 to 40 weeks' gestational age was examined. Functional activity of the adrenal cortex was followed by analysis of the zonal distribution of lipids and by measurement of the total cholesterol content. The cholesterol content ranged between 0.15 and 0.85 mg/100 g. Cholesterol accumulation was highest in the anencephalic monsters. The relative cholesterol content failed to show any correlation with gestational age. When compared with the biochemical determination of cholesterol content, morphological investigation of lipid accumulation proved to be superior and to be a suitable method for estimation of zonal maturity even in individual cases.
Histological slides of the adrenals of 54 patients who underwent uni- or bilateral adrenalectomy for Cushing's syndrome at the Zürich University Hospital Department of urology between 1960 and 1977 were reexamined. In 29 patients (53.7%) Cushing's disease was due to diffuse bilateral adrenocortical hyperplasia, in 4 (7.4%) to micronodular cortical hyperplasia and in 3 (5.6%) to macronodular cortical hyperplasia and in 3 (5.6%) to macronodular hyperplasia. Two patients (3.7%) presented with primary bilateral nodular cortical dysplasia (so-called microadenomatosis). In 12 cases of Cushing's syndrome (22.2%) the basic lesion was a cortical adenoma and in 4 cases (7.4%) a cortical carcinoma. The histologic diagnoses corresponded well with biochemical findings, clinical diagnoses and further development of the disease. Histopathologic diagnosis of diffuse and micronodular hyperplasia presents no difficulties. Differential diagnosis of macronodular hyperplasia, cortical dysplasia, adenoma, and carcinoma may, however, be somewhat more problematic.
A stratum of cells that did not contain both aldosterone synthase cytochrome P450 (cytochrome P450aldo) and cytochrome P45011 beta was found immunohistochemically between the zona glomerulosa and the zona fasciculata of the rat adrenal cortex. As cytochromes P450aldo and P45011 beta are the enzymes responsible for the biosynthesis of aldosterone and corticosterone, respectively, the cells there are considered to be incapable of synthesizing both aldosterone and corticosterone. Furthermore, the cells are regarded as inert in producing adrenal androgens, because rat adrenal cortex is known to lack steroid 17 alpha-hydroxylase. Thus, the stratum is composed of cells that do not synthesize any of the major corticosteroids in significant quantities. It was 5-10 cells thick under normal feeding conditions, but diminished to 4-5 cells thick when animals were maintained under Na restriction, which is known to stimulate the secretion of angiotensin-II. When the distribution of 5-bromo-2'-deoxyuridine-labeled nuclei in the adrenocortex from BrdU-administered rats was examined, the stained nuclei were concentrated in and around the cell stratum. The pulse-chase experiments showed that the labeled cells migrated out of this layer and into the zonae fasciculata-reticularis. On the basis of these findings, we suggest that the newly discovered cell layer is the progenitor cell zone of the rat adrenal cortex.
Explore the source record for details and available documents.
Activity of glutamate decarboxylase, a GABA synthesis enzyme, and intensity of its reception in the adrenal cortex and hypothalamus of guinea pigs and rats with normal and stimulated steroidogenesis was investigated. It has been shown that in the adrenal cortex there is a metabolic system which provides GABA synthesis from glutamate and mechanisms of GABA reception by plasmatic membranes. Mediator synthesis in the adrenal cortex is subjected to seasonal changes, GABA synthesis and reception selectively vary with administration of ACTH, prolactin and maintenance of animals on a diet with an excess of potassium ions.
The influence of ethane dimethanesulfonate (EDS), a specific toxicant for Leydig cells, on the morphometric characteristic of adult male rat adrenal cortex was examined on day 15 after administration. As expected, the dose of 75 mg kg-1 of EDS produced drastic reduction in serum testosterone levels followed by a decrease in testis and seminal vesicle weight. However, a considerable drop (over 50%) in adrenal weight was also found. Stereological analysis of the adrenal cortex, performed under light microscope, revealed atrophy of all adrenocortical zones. The changes were most prominent in the inner zones. Thus, in the zona fasciculata the number of parenchymal cells was markedly decreased. In the zona reticularis a layer consisting mostly of atrophic parenchymal cells was localised at the border between zona reticularis and zona fasciculata. The remaining small number of cortical cells in this zone displayed a notable hypertrophy. It is concluded that EDS at a dose that destroys Leydig cells has a strong deleterious effect on steroidogenic cells of adult male rat adrenal cortex.
The control of zonation in the adrenal cortex has been studied by measuring DNA synthesis using an analogue of thymidine, bromodeoxyuridine (BrDUrd). Groups of rats were infused with BrDUrd for 10-14 days whilst being treated with: high or low sodium diets; captopril; angiotensin II; dexamethasone; an inhibitor of nitric oxide synthesis, L-NAME. DNA synthesis in the zona glomerulosa was increased by low sodium food and angiotensin and was decreased by dexamethasone, captopril L-NAME and a high sodium diet. Dexamethasone, not manipulations of the renin-angiotensin system, affected DNA synthesis in the outer zona fasciculata. The BrDUrd index in the zona intermedia was unaffected by any of the treatments and was generally lower than in adjacent zona fasciculata and zona glomerulosa cells. Cells of the zona reticularis appeared to be regulated independent of the zona fasciculata. BrDUrd uptake in nuclei of the adrenal medulla was inversely related to blood pressure. We conclude that DNA synthesis in each adrenocortical zone is independently controlled. Migration of cells within zones after proliferation is likely.
Dopamine may be a modulator of aldosterone secretion in man. Whether this effect is extraadrenal or is exerted directly at the adrenal gland via local dopaminergic receptors remains uncertain. This study examined the possibility that dopaminergic binding sites exist in the human adrenal cortex using [3H]spiperone, a butyrophenone with high affinity for dopaminergic receptors of the D2 subtype. [3H]Spiperone binding to membranes prepared from the outer adrenal cortex obtained from eight patients undergoing adrenalectomy was studied. Specific [3H]spiperone binding, defined as binding displacable by 250-fold excess of unlabeled spiperone reached equilibrium within 30 minutes at 4 degrees C and was readily reversible. Binding was consistent with both high affinity (Kd1 = 0.2 to 0.8 nmol/L) and low affinity (Kd2 = 20 to 127 nmol/L) binding states. Binding capacity was 27 to 276 fmol/mg for the high affinity and 63 to 597 fmol/mg for the low affinity binding state. The relative potency in inhibition of [3H]spiperone binding was as follows: antagonists, spiperone greater than domperidone greater than metoclopramide greater than ketanserin greater than (-) sulpiride greater than (+) sulpiride; agonists, dopamine, bromocriptine greater than NPA much much greater than epinephrine. Serotonin and norepinephrine did not affect [3H]spiperone binding. These data suggest the existence of dopaminergic binding sites possibly of the D2 subtype in the human adrenal cortex. The precise location of these sites remains to be determined.