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This study examined the role of endothelins (ETs) and their receptor subtypes ETA and ETB in the regulation of vascular tone in the in situ perfused rat left adrenal gland. Endothelin-1 (ET-1), which binds both ETA and ETB receptors, decreased adrenal flow rate of the perfusion medium, and its effect was reversed by the ETA antagonist BQ-123 and enhanced by the ETB antagonist BQ-788. ET-3, which preferentially binds ETB, and the selective ETB agonist BQ-3020 increased adrenal flow rate of perfusate, and their effects were annulled by BQ-788. BQ-123 magnified the effect of ET-3 and did not affect that of BQ-3020. The ETA-mediated decrease and the ETB-mediated rise in the rate of collection of perfusate were abolished by Ro-31-8220, an inhibitor of protein kinase C (PKC), and by N(G)-nitro-L-arginine methyl ester, an inhibitor of nitric oxide synthase (NOS), respectively. Collectively, these findings suggest that ETs can regulate vascular tone in the in situ perfused rat adrenals via both PKC-coupled ETA and NOS-coupled ETB receptors, the activation of which evokes vasoconstriction and vasodilation, respectively.

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The effects of a 7-day intraperitoneal infusion with VIP (0.03 nmol.kg-1.min-1) and its antagonist [4-Cl-D-Phe6,Leu17]-VIP (VIP-A; 3 nmol.kg-1.min-1) were studied in sham and bilaterally adrenalectomized rats bearing ACTH and angiotensin II (ANG-II)-responsive adrenocortical autotransplants. VIP significantly increased plasma aldosterone (ALDO) concentration (PAC) and lowered plasma renin activity (PRA) in both groups of animals, without affecting plasma levels of ACTH and corticosterone. This treatment caused a marked hypertrophy of adrenal zona glomerulosa (ZG) and its parenchymal cells (without inducing any significant change in the zona-fasciculata morphology), as well as of ZG-like cells of autotransplants. Isolated ZG cells and autotransplant quarters obtained from VIP-infused rats evidenced a notable increase in both their basal and maximally ACTH- or ANG-II-stimulated ALDO secretion. The simultaneous infusion of rats with VIP-A completely reversed all these effects of VIP. The infusion with VIP-A alone caused, in sham-operated rats, a net decrease in PAC, coupled with a rise in PRA, and a marked atrophy of ZG and ZG cells; basal and maximally stimulated ALDO secretion of dispersed ZG cells was also significantly lowered. Conversely, VIP-A did not evoke any appreciable effect in autotransplanted rats. These findings suggest that endogenous VIP is specifically involved in the maintenance of the growth and secretory capacity of rat adrenal ZG. Since regenerated adrenocortical autotransplants, which are responsive to VIP but not to VIP-A infusion, are completely deprived of chromaffin cells, the hypothesis is advanced that adrenal medulla may be the source of endogenous VIP regulating ZG function.

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The effect of SRIF and its antagonist cyclo(7-aminoheptanonyl-Phe-D-Trp-Lys-Thr magnitude of Bzl)(SRIF-A) were studied in sham-operated and bilaterally adrenalectomized rats bearing ACTH- and angiotensin II (ANG-II)-responsive adrenocortical autotransplants. SRIF-A (10(-5) M) completely annulled SRIF (10(-6) M)-induced inhibition of ANG-II (10(-8) M)-evoked rise in aldosterone (ALDO) secretion by both dispersed zona glomerulosa (ZG) cells and autotransplant slices. A 7-day intraperitoneal infusion with SRIF (0.3 nmol.kg-1.min-1) significantly lowered plasma ALDO concentration (PAC) in both groups of animals, without affecting plasma renin activity and the plasma levels of ACTH and corticosterone. This treatment caused a marked atrophy of adrenal ZG and its parenchymal cells (without inducing any significant change in the zona fasciculata morphology), as well as of ZG-like cells of autotransplants. Isolated ZG cells and autotransplant slices from SRIF-infused rats evidenced a notable decrease in both their basal and maximally ACTH- or ANG-II-stimulated ALDO production. The simultaneous infusion of rats with SRIF-A (3 nmol.kg-1.min-1) completely reversed all these effects of SRIF. The prolonged infusion with SRIF-A alone caused, in sham-operated rats, a marked increase in PAC and a significant hypertrophy of ZG and ZG cells; basal and maximally-stimulated ALDO secretion of dispersed ZG cells was also notably raised. Conversely, SRIF-A infusion did not evoke any appreciable effect in autotransplanted rats. These findings suggest that endogenous SRIF is specifically involved in the negative control of the secretion and growth of the rat adrenal ZG. Since regenerated adrenocortical autotransplants, which are responsive to SRIF but not to SRIF-A infusion, are completely deprived of chromaffin cells, the hypothesis is advanced that adrenal zona medullaris may be the source of endogenous SRIF regulating ZG function.

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Rat adrenocortical autotransplants regenerated from capsular-tissue fragments implanted in the musculus gracilis displayed an in-vitro basal gluco- and mineralocorticoid secretion qualitatively similar to that of adrenal quarters from control rats. Moreover, like adrenal quarters, they responded to angiotensin-II (Ang-II, 10(-8) M) by raising their yield of 18-hydroxylated steroids (18-hydroxy-11-deoxycorticosterone, 18-hydroxycorticosterone and aldosterone). ANP (10(-8) M), one of the main negative modulators of the zona-glomerulosa (ZG) mineralocorticoid secretion, totally blocked the ANG-II stimulating effect on adrenal quarters, but not that on adrenocortical autotransplants. Autoradiography showed that, in contrast with ZG cells of control rats, ZG-like cells of transplants did not significantly bind 125I-ANP. The hypothesis is discussed that ZG-like cells of regenerated adrenocortical nodules lack specific receptors for ANP.

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CRH and ACTH immunoreactivities (ir) were present in rat adrenal glands but not in adrenocortical autotransplants lacking chromaffin cells. Interleukin-1beta (IL-1beta) dose-dependently elicited CRH-ir and ACTH-ir release by decorticated adrenal fragments mainly composed of zona-medullaris tissue; the minimum effective concentration was 10(-10)/10(-8)M, and the maximal one was 10(-6)M. The IL-1beta (10(-6)M)-induced ACTH release by our preparations was completely blocked by alpha-helical-CRH (10(-6)M), a competitive inhibitor of CRH. These findings suggest that chromaffin medullary cells of the rat adrenals contain a CRH/ACTH system, duplicating that operating at the hypothalamohypophyseal level, which is stimulated by IL-1beta. Thus, the mechanism underlying the well-known glucocorticoid secretagogue effect of interleukins may involve the activation of both the central and the peripheral branch of the hypothalamohypophyseal-adrenal axis.

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A case of removal of a fetus in fetu in a 47-year-old man is reported. The patient had an upper abdominal mass since birth that had never caused any subjective symptoms. A preoperative computed tomographic scan was useful to confirm the diagnosis. The operative specimen consisted of a cystic mass about 20 cm in diameter, situated in the upper retroperitoneal space. The cyst was full of a yellowish fluid and hairs. A bony structure, about 10 cm in diameter, contained a vertebral axis connected to the ribs and was adherent to the cystic wall. To our knowledge this is the first reported case of fetus in fetu described in an adult man. The tumor, present for 47 years, did not grow or cause any complications and did not show any sign of malignancy.

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1. The effect of bilateral adrenalectomy on the sensitivity of blood vessels in rat airways to mediators that increase vascular permeability was examined. 2. An increase in vascular permeability was induced by intravenous platelet activating factor (PAF, 50, 100, 500, 1000 ng kg-1) and measured by quantifying the extravasation of Evans blue dye. 3. PAF consistently increased the amount of Evans blue extravasation in the larynx, trachea, main bronchi and intrapulmonary airways in sham-operated rats. 4. The magnitude of this extravasation was significantly greater in the larynx (P less than 0.05), trachea (P less than 0.05) and main bronchi (P less than 0.05) of the adrenalectomized rats than it was in these tissues of the sham-operated rats. 5. When adrenalectomized rats were given subcutaneous dexamethasone (0.2 mg kg-1 4 h before PAF) the amount of plasma extravasation produced by PAF was decreased to the level of the sham-operated rats. 6. We conclude that adrenalectomy potentiates the increase in airway vascular permeability induced by PAF in rats and that this effect may be due to the depletion of endogenous corticosteroids.

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Regenerated adrenocortical nodules were obtained by implanting fragments of the capsular tissue of excised adrenal glands into the musculus gracilis of rats (Belloni et al. 1990). Five months after the operation, operated rats showed a normal basal blood level of corticosterone, but a very low concentration of circulating aldosterone associated with a slightly increased plasma renin activity (PRA). Regenerated nodules were well encapsulated and some septa extended into the parenchyma from the connective-tissue capsule. The majority of parenchymal cells were similar to those of the zonae fasciculata and reticularis of the normal adrenal gland, while zona glomerulosa-like cells were exclusively located around septa (juxta-septal zone; JZ). In vitro studies demonstrated that nodules were functioning as far as glucocorticoid production was concerned, while mineralocorticoid yield was very low. Prolonged sodium restriction significantly increased PRA and plasma aldosterone concentration, and provoked a marked hypertrophy of JZ, which was due to increases in both the number and average volume of JZ cells. Accordingly, the in vitro basal production of aldosterone and other 18-hydroxylated steroids was notably enhanced. The plasma level of corticosterone, as well as zona fasciculata/reticularis-like cells and in vitro production of glucocorticoids by regenerated nodules were not affected. These findings, indicating that autotransplanted adrenocortical nodules respond to a prolonged sodium restriction similar to the normal adrenal glands, suggest that the relative deficit in mineralocorticoid production is not due to an intrinsic defect of the zona glomerulosa-like JZ, but is probably caused by the impairment of its adequate stimulation under basal conditions.(ABSTRACT TRUNCATED AT 250 WORDS)

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Regenerated adrenocortical nodules were obtained by implanting in the musculus gracilis of rats fragments of the capsular tissue of their excised adrenal glands. Five months after operation, transplanted rats showed a slightly elevated blood concentration of adrenocorticotropin (ACTH), a moderately reduced plasma level of corticosterone (PBC) and a very low concentration of circulating aldosterone (PAC). Regenerated nodules were well encapsulated, and from the connective capsule some septa dipped into the parenchyma. Subcapsular-outer (OZ) and inner (IZ) cells were similar to those of the zona fasciculata/zona reticularis (ZF/ZR) of the normal gland; juxta-septal (JZ) cells resembled those of the zona glomerulosa (ZG). Prolonged (14 days) ACTH infusion normalized PBC and caused a conspicuous hypertrophy of transplanted tissue, which was coupled with a marked hypertrophy of ZF/ZR-like OZ and IZ cells and a notable rise in the basal in vitro production of corticosterone. Conversely, ACTH infusion strikingly lowered PAC, reduced the number of ZG-like JZ cells, and decreased both basal and stimulated secretion of 18-hydroxylated steroids by transplants in vitro.

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This paper describes the function and morphology of regenerated adrenocortical nodules obtained by implanting, in the musculus gracilis of rats, several (n = 6-7) fragments of the capsular tissue of their excised adrenal glands. Four months after the operation, each bilaterally adrenalectomized rat developed six or seven well encapsulated adrenocortical nodules about 2-3 mm in diameter and always lacking chromaffin cells, and displayed almost complete normalization of basal and stimulated blood levels of corticosterone, but not of aldosterone. In vitro study showed that regenerated nodules were well functioning as far as glucocorticoid production was concerned. Accordingly, electron microscopy and stereology indicated that the majority of the parenchymal cells (independently of their location in the outer subcapsular, middle, or inner portions) closely resembled those of the zonae fasciculata/reticularis of the adrenal gland of age-matched sham-operated rats. By contrast, regenerated nodules evidenced a relative impairment in aldosterone secretion, and this was coupled with the presence of only a few zona glomerulosa-like cells. Such cells were grouped in small islets located near the few connective trabeculae detaching from the capsule, and autoradiography showed that they were the only parenchymal elements of the nodule able to bind [125I]angiotensin-II. The possibility is suggested that the paucity of zona glomerulosa-like cells in regenerated nodules could be ascribed to the absence of zona medullaris, which is currently thought to exert a paracrine control on the growth and secretion of zona glomerulosa in the rat adrenal glands.

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The authors present their experience with 5 biliary cystadenomas (BCA) and 1 cystadenocarcinoma (BCAC). BCA are rare but intriguing lesions of the liver for the possibility of the former to evolve into malignant lesion. Preoperative diagnosis is often difficult also at ultrasound and CT scan. The possibility of BCA and BCAC should be always ruled out in every cystic lesion of the liver. In every doubt lesion surgical exploration is indicated and at least a biopsy should be performed. The procedure of choice for BCA is radical resection, while palliative procedures may be justified only in poor risk patients.

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The development of major hepatic resective surgery during the last 50 years is due to a better knowledge of both hepatic regenerative capacity and intraparenchymal vascular and biliary anatomy. Two approaches of major hepatic resection have been described: 1) primary hilar approach; 2) primary transparenchymal approach. The authors review the indications of major hepatic resections in the treatment of hepatic tumors and discuss the advantages and the disadvantages of primary hilar and primary transparenchymal approaches, reviewing the data from the literature and the experience gained at the Clinica Chirurgica of the University of Verona from 1970 to 1989 of 289 major hepatic resections.

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The presence of tubercle of Zuckerkandl (TZ) of the thyroid gland has been investigated in 20 specimens obtained from patients died from diseases not concerned to the cervical area. The project mas undertaken to elucidate the presence and the role of TZ as normal anatomical landmark. Special attempt has been paid to the relationships of the TZ with parathyroid gland and recurrent laryngeal nerve and the branches of the inferior thyroid artery. The tubercle was constantly found on the postero-medial surface of the thyroid lobe which showed constant relations with the branches of the inferior thyroid artery, superior parathyroid gland and recurrent laryngeal nerve. The outcomes of this preliminary report prove that TZ is an useful anatomical landmark to detect both superior parathyroid gland and laryngeal nerve in thyroid surgery.

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