Carlo Macchi

Effects of oxytocin on the function and morphology of the rat adrenal cortex: in vitro and in vivo investigations

The effects of oxytocin (OX) on the function and morphology of the rat adrenal cortex were studied in vivo and in vitro. OX exerted a potent stimulatory action on basal, but not 10−8 M ACTH-stimulated corticosterone (B) secretion of dispersed rat inner (zona fasciculata and zona reticularis) adrenocortical cells (maximal effective concentration: 10−9 M); in contrast, at higher concentrations (10−7/10−6 M) OX inhibited maximally ACTH-stimulated B output. A single subcutaneous (s.c.) injection of 1.2 nmol/100 g body weight OX resulted in a longlasting (up to 12 h) rise in plasma B concentration (PBC). The prolonged administration of OX (daily s.c. injections of 0.6 or 1.2 nmol/100 g for 10 days) caused a marked lowering in the adrenal weight and volume of all adrenocortical zones, that in turn was due to a decrease in the number of their parenchymal cells; however, the average volume of inner adrenocortical cells was significantly increased. Basal PBC was lowered, but its response to ether stress was unchanged in comparison with control rats. Prolonged OX treatment did not change B secretion by adrenal slices, but it markedly raised that of dispersed inner adrenocortical cells. Our present findings clearly show that the effects of OX on the adrenal cortex depend on the experimental model employed (in vitro versus in vivo) and the duration of treatment (acute versus chronic). Taken together they allow us to conclude that OX exerts an acute direct stimulatory effect on the rat adrenal cortex, and a chronic inhibitory one, that at least in part could be due to the interference of OX with the mechanism(s) of intracellular transduction of the ACTH secretagogue signal.

Cerebellin stimulates the secretory activity of the rat adrenal gland: in vitro and in vivo studies.

Cerebellin is a 16-aminoacid peptide widely distributed in the central nervous system, where it exerts neuromodulatory functions. Cerebellin is contained in human adrenal medulla, and it has been recently demonstrated that cerebellin elicits catecholamine release by human adrenal in vitro. Aim of the present study was to ascertain whether cerebellin affects adrenal function in the rat. Cerebellin concentration-dependently (from 10(-9)to 10(-7)M) increased norepinephrine (but not epinephrine) and cyclic-AMP production by adrenomedullary tissue in vitro. The norepinephrine response to 10(-7)M cerebellin was blocked by the protein kinase (PK) A inhibitor H-89, but not by the phospholipase C inhibitor U-73122 or the PKC inhibitor calphostin-C. Cerebellin did not affect aldosterone and corticosterone secretion of dispersed zona glomerulosa and zona fasciculata-reticularis adrenocortical cells. Cerebellin concentration-dependently (from 10(-8)to 10(-7)M) enhanced norepinephrine release by in situ perfused rat adrenals. Cerebellin (10(-7)M) also elicited a significant rise in aldosterone and corticosterone output, and this effect was annulled by either the beta1-adrenoceptor antagonist l -alprenolol or H-89. Collectively, the present findings allow us to conclude that cerebellin 1) directly stimulates norepinephrine release via the adenylate cyclase/PKA-dependent signaling pathway; and 2) indirectly enhances adrenocortical secretion in vivo, through a paracrine mechanism involving medullary catecholamine release.

Acute effects of recombinant murine leptin on rat pituitary-adrenocortical function.

Leptin, the product of the ob gene, is an adipose-tissue secreted hormone, which regulates satiety, metabolic rate and thermogenesis. Many lines of evidence suggest the existence of mutual relationships between leptin and adrenal-cortex secretion, but in vivo studies gave rather conflicting results. Therefore, we have investigated the acute effect of the systemic bolus administration of leptin (5 or 10 nmol/kg) on the function of rat pituitary-adrenocortical function. The blood concentrations of ACTH, aldosterone and corticosterone were measured by specific RIA 60 or 120 min after the leptin injection. Leptin did not affect the blood concentrations of ACTH and aldosterone at 60 min, but at 120 min the lower dose of the peptide increased them. In contrast, the blood level of corticosterone was markedly enhanced by both doses of leptin at 60 and 120 min. Collectively, these findings indicate that leptin exerts a moderate acute activation of the pituitary-adrenocortical function in rats. They also suggest that the adrenocortical secretagogue action of leptin is not only mediated by the enhanced pituitary ACTH release, but is also consequent to a direct stimulatory effect of the peptide on adrenocortical cells.

Further investigations on the effects of neuropeptide Y on the secretion and growth of rat adrenal zona glomerulosa

NPY is a regulatory peptide, high levels of which are contained in adrenal glands of several mammals and which is co-released with catecholamines during various stressful conditions. The acute and chronic effects of NPY on adrenocortical secretion and growth were studied in the rat. NPY concentration-dependently increased aldosterone (ALDO), but not corticosterone (B) secretion of adrenal slices (maximal effective concentration was 10(-7) M). Two competitive inhibitors of NPY receptors, named PYX-1 and PYX-2, were found to dose-dependently inhibit ALDO response of adrenal preparations to 10(-7) M NPY; PYX-2 was more efficient than PYX-1, and at a concentration of 10(-5) M completely annulled the effect of 10(-7) M NPY. The acute bolus intraperitoneal (i.p.) injection of NPY (3 nmol/kg) raised plasma ALDO concentration (PAC), but not that of B (PBC); this effect of NPY was blocked by the simultaneous injection of PYX-2 (300 nmol/kg). The prolonged i.p. infusion with NPY (3 nmol/kg/h for 7 days) increased PAC (but not PBC) and induced a marked hypertrophy of the zona glomerulosa (ZG) and its parenchymal cells; dispersed ZG cells obtained from NPY-infused rats displayed a significantly enhanced basal and maximally agonist-stimulated ALDO production. The simultaneous infusion with PYX-2 (300 nmol/kg/h) completely annulled all these effects of NPY. The acute or chronic administration of PYX-2 alone did not evoke any apparent effect on the ZG secretion and growth. In light of these findings the following conclusions can be drawn: (i) NPY is able to stimulate not only the secretion, but also the growth of adrenal ZG in rats, via a receptor-mediated mechanism (since this effect is blocked by PYX-2); (ii) endogenous NPY does not play a prominent role in the physiological maintenance of secretion and growth of rat ZG (since PYX-2 alone is ineffective); (iii) NPY may play a crucial role in the fine tuning of the ZG functions in conditions requiring an increased release of mineralocorticoid hormones.

Adrenocortical oncocytoma: case report and review of the literature.

Only 9 oncocytic neoplasms of true adrenal origin have been described to date. It therefore seemed of interest to study the histochemical and ultrastructural features of a non-functioning monolateral adrenocortical oncocytoma which was incidentally detected by ultrasonography and magnetic resonance imaging in a 28-year-old woman. The tumor was round, well encapsulated and weighed 73 g. It consisted of islets of eosinophilic cells, and did not display any sign of necrosis. The proliferation rate (as evaluated by mitotic index and percentage of MIB-1 Ki67 positive cells) was low, and atypic mitoses were absent; some rare cells with nuclear atypias were observed and the capsule was focally invaded by oncocytes. Immunocytochemistry did not show expression of vimentin or cytokeratin. The oncocytes had an abundant cytoplasm packed with mitochondria containing plate-like cristae. Smooth endoplasmic reticulum was virtually absent, while rough endoplasmic reticulum cisternae and free ribosomes were abundant. Although the classic histological approach clearly indicates the benign nature of the tumor, the immunocytochemical and ultrastructural features of oncocytes may suggest their potential for malignant behavior.

Evidence that endogenous substance-P (SP) is involved in the maintenance of the growth and steroidogenic capacity of rat adrenal zona glomerulosa

A 7-day intraperitoneal infusion with the specific SP antagonist magnitude of D-Pro4,D-Trp7,9-SP4-11 (SP-A; 0.3 nmol.kg-1.min-1) significantly lowered plasma aldosterone (ALDO) concentration and caused atrophy of adrenal zona glomerulosa (ZG) and its parenchymal cells. Dispersed ZG cells from SP-A-infused rats displayed a marked decrease in both their basal and maximally agonist-stimulated ALDO production. The simultaneous infusion of rats with SP (0.03 nmol.kg-1.min-1) completely annulled all these effects of SP-A. The plasma levels of ACTH and corticosterone, and the morphology of adrenal zona fasciculata were not affected by SP-A or SP-A plus SP infusion. These findings suggest that endogenous SP is specifically involved in the positive control of growth and secretion of the rat ZG.

Effects of neuromedin-k on the rat hypothalamo pituitary-adrenal axis

The effects of neuromedin-K (NMK) on the rat hypothalamo-pituitary-adrenal (HPA) axis were studied both in vivo and in vitro. A subcutaneous injection of 1 nmol/100 g NMK evoked a rise in plasma ACTH level at 30 min, increased plasma corticosterone (B) concentration (PBC) at 60 and 120 min, and did not alter plasma aldosterone (ALDO) concentration (PAC). The administration of 3 nmol/100 g NMK induced a rise in plasma ACTH level at 120 min and a drop of PBC at 30 min; it increased PBC and PAC at 60 and 120 min. NMK did not affect basal B secretion of dispersed zona fasciculata/reticularis (ZF/R) cells, but markedly enhanced basal ALDO production by dispersed zona glomerulosa (ZG) cells (minimal and maximal effective concentrations were 10(-9) M and 10(-7) M). Video-imaging analysis showed that NMK (10(-8) M) increased intracellular Ca2+ concentration in dispersed ZG cells, but not in ZF/R ones. These findings indicate that NMK exerts a complex modulatory action on the rat HPA axis: low doses of NMK appear to evoke a transient stimulation of ACTH release, while high doses seem to exert a short-term inhibition of glucocorticoid synthesis followed by the compensatory hypersecretion of ACTH; moreover, elevated doses of NMK also exert a strong ALDO secretagogue action by acting directly on the ZG cells.

Adrenocortical Oncocytoma: Case Report and Review of the Literature

Only 9 oncocytic neoplasms of true adrenal origin have been described to date. It therefore seemed of interest to study the histochemical and ultrastructural features of a non-functioning monolateral adrenocortical oncocytoma which was incidentally detected by ultrasonography and magnetic resonance imaging in a 28-year-old woman. The tumor was round, well encapsulated and weighed 73 g. It consisted of islets of eosinophilic cells, and did not display any sign of necrosis. The proliferation rate (as evaluated by mitotic index and percentage of MIB-1 Ki67 positive cells) was low, and atypic mitoses were absent; some rare cells with nuclear atypias were observed and the capsule was focally invaded by oncocytes. Immunocytochemistry did not show expression of vimentin or cytokeratin. The oncocytes had an abundant cytoplasm packed with mitochondria containing plate-like cristae. Smooth endoplasmic reticulum was virtually absent, while rough endoplasmic reticulum cisternae and free ribosomes were abundant. Although the classic histological approach clearly indicates the benign nature of the tumor, the immunocytochemical and ultrastructural features of oncocytes may suggest their potential for malignant behavior.

Friar Leopoldo Mandic (1866–1942): the computed tomography of the body of a Saint

Post-mortem Computed tomography (CT) is an imaging technique for documentation and analysis of consecutive autopsy findings, including fractures and gross tissue injuries. Various post-processing techniques can provide strong forensic evidence for use in legal proceedings. On the other hand, this technique is implied also in paleopathology, in particular in mummy studies, with the aim of providing a permanent record of the mummy’s features, investigating the embalming procedure employed and analyzing the extent of the preservation in detail. For the Extraordinary Jubilee of Mercy, the mortal remains of Saint Leopoldo Mandic and Saint Pio da Pietrelcina, as examples of Mercy known by everyone, have been brought to Rome from 3 to 11 February. During the survey that preceded the preparation for transport to Rome, a whole-body CT was performed on the mummified corpse of Leopoldo Mandic, Capuchin Saint of Padova, Italy. The CT examination demonstrated the presence of arthritis at the level of the vertebral column, of the left knee and of the hand. Moreover, CT showed the preservation of skeleton, and partial preservation of the brain, ear ossicles, major arterial vessels (aorta and carotid arteries), pleurae, esophagus, heart, urinary bladder, nervous structures (plexuses and spinal nerves). Pseudo-pathologic changes, primarily postmortem skeletal dislocations were also present at the level of the hip joints. It is to emphasize the fact that San Leopoldo was not subjected before the CT to any conservative treatment, with the exception of a surface treatment with celluloid. CT demonstrated to be a non-destructive method to investigate Saint Leopoldo, in order to maintain the integrity of the body and to acquire data on his pathologies and on his preservation. CT allows not only the acquisition of sectional images but also, thanks to dedicated software, the post-processing and reconstruction of three-dimensional models, that can be used also for public displays.

Hallux valgus and fusion of the middle phalange of vray

Hallux valgus (HV) is a foot deformity commonly seen in medical practice, often accompanied by significant functional disability and foot pain. Its prevalence in the adult population is in 23% in adults (18-65 years) and 35.7% in elderly people (over 65 years) and is higher in females (30% compared to males 13%). The anatomical variation of the lateral rays has been ascribed to the process of involution of the feet and of its functions and actions. The intermediate phalanges of the V ray can be fused or also reduced in volume. The aim of the study was to evaluate a possible association between HV and anatomical variation of V ray. The standard radiographs of 100 patients (M 21, F 79, mean age 53y) with clinical diagnosis of HV were analysed. The HV angle was 29.84 (range 16.9 - 62,5), the 1-2 intermetatarsal angle was 10.92 (range 6.93-16.63) and the hallux interphalangeal angle was 10.55 (range 1,8 – 35.3). In 98% of cases there was the presence of fusion of the phalanges. A series of 100 consecutive patients (M 25, F 75, mean age 48y) were also analysed and basing on the review of the standard radiographs the fusion of the middle phalange was found in 42% of cases. There are conflicting notions about aetiology of HV as well. Occupation, shoe wear, genetic predisposition, and pes planus have been implicated. Our study show a strong association between the HV and fusion of the middle phalange. The presence of an anatomical variation of the V ray could modify the biodynamic of the walk and consequently influence the development and progression of the HV.