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Notes: Phenylephrine increased [3H]norepinephrine efflux and accumulation of cyclic AMP in cultured rat superior cervical ganglion cells supervised with Tyrode's solution. The purpose of this study was to determine the mechanism and relationship between these two events. Electrical stimulation (1–2 Hz), potassium chloride (50 mM), and the preferential α1-adreneargic receptor agonist phenylephrine (1–100 μM) increased fractional tritium efflux, whereas methoxamine, cirazoline, and amidephrine were relatively ineffective. Phenylephrine, but not methoxamine and cirazoline, also iacreased cyclk AMP accumulation. Phenylephrine-induced tritium efflux was not altered by α-and β-adrenergic receptor antagonists or by removal of extracellular calcium. Phenylephrine-induced cyclic AMP accumulation was blocked by the β-adrenergic receptor antagonists propranolol and atenokd. Focskolin (10 μM) and the nonhydrolyzable cyclic AMP analogue 8-(4-chlorophenylthio)cyclic AMP (100 μM) had minimal effect on tritium efflux. However, phenylephrine-evoked increase in tritium efflux was dose dependency attenuated by the neuronal uptake blocker cocaine, and phenylephrine dose-dependently inhibited the incorporation of [3H]norepinephrine into neuronal stores. We conclude that the increase in tritium efflux induced by Phenylephrine is independent of cyclic AMP accumulation and appears to be mediated by uptake of phenylephrine via the neuronal carrier-mediated amine transport process, which in tarn promotes efflux of the adrenergic transmitter from its storage sites.

Notes: The aim of this study was to investigate whether increased oxidative stress occurs in erosive lichen planus of the vulva. Skin biopsies from six patients with untreated, histologically confirmed erosive lichen planus of the vulva were examined immunohistochemically using antibodies against antioxidant enzymes. The protein-bound lipid peroxidation products malondialdehyde (MDA) and 4-hydroxynonenale (4-HNE) and the oxidative DNA damage marker 8-hydroxy-2′-deoxyguanosine (8-OHdG) were investigated. Protein carbonyls as markers of protein oxidation were visualised using the dinitrophenylhydrazone (DNPH) method. Normal vulval tissues from 12 subjects served as controls. In vulval lichen planus tissue the enzymatic antioxidant defence was found to be significantly decreased in the epidermal layers. Furthermore, a significant increase of lipid peroxidation products and oxidative DNA damage was found within the epidermis. Protein oxidation occurred predominantly in the papillary dermis. This is the first study to demonstrate a decreased antioxidant defence and increased oxidative damage to lipids, DNA and proteins in lichen planus. These oxidative modifications point to pathophysiological alterations mainly within the basal cell layers of the epidermis and at the dermoepidermal junction. Further studies are warranted to investigate the potential role of oxidative stress in the development of autoimmunity in this disease.

Notes: Paraneoplastic pemphigus is a relatively recently described immunobullous disease with characteristic features. We report three cases of paraneoplastic pemphigus in adult men with chronic lymphocytic leukaemia arising within a week of completion of treatment with fludarabine. In all cases, withdrawal of fludarabine and treatment of the blistering was associated with marked cutaneous improvement. Fludarabine, a synthetic nucleoside analogue, which has only been available in Britain since 1994, is known to be associated with autoimmune phenomena and may have been involved in the development of paraneoplastic pemphigus in these cases.

Notes: Summary Acantholysis is a feature of disorders such as Hailey-Hailey disease and Darier's disease. Immunocytochemical studies have shown internalization of desmosomal components after acantholysis. Basal cytokeratins show suprabasal expression in lesional Darier's disease. The exact mechanisms of acantholysis are still unclear. Cantharidin induces blistering, with suprabasal keratinocyte acantholysis, possibly by protease activation. Plasmin has been implicated in the pathogenesis of acantholysis in Darier's disease and Hailey-Hailey disease. We examined the distribution of desmosomal components, proteases and cytokeratins in cantharidin blisters, to compare them with those previously found in Darier's disease and Hailey-Hailey disease. Two drops of cantharidin collodion were applied to the skin of five normal volunteers. A 4-mm punch biopsy of the blister was taken, and snap frozen. Sections were stained with antibodies to desmosomal proteins (dp) 1/2, dp 3, desmosomal glycoproteins (dg) 1, 2/3, extracellular carbohydrate residues, using the lectins peanut agglutinin (PNA) and soybean agglutinin (SBA), proteases and cytokeratins. Acantholytic cells were stained diffusely with dp l/2: there was markedly reduced or absent peripheral staining for dp 3, dg l, dg 2/3, PNA and SBA. There was no clumping of stain. Plasminogen, fibrinogen and urokinase were expressed in some acantholytic cells. Basal keratin markers were expressed suprabasally in acantholytic cells. These results are similar to those previously obtained in Darier's disease, but different from the staining obtained in Hailey-Hailey disease. Extracellular glycosylated portions of adhesion molecules may be lost after acantholysis, perhaps as a result of conformational changes, internalization of extracellular domains, or proteolysis. The changes in the expression of plasminogen, fibrinogen, urokinase and cytokeratins in acantholytic cells in cantharidin-induced blisters are, as in Darier's disease and Hailey-Hailey disease, probably secondary to acantholysis, and changes in the shape of cells. We conclude that cantharidin blisters may be a useful model for the study of acantholysis in Darier's disease.

Notes: Pemphigus vulgaris (PV) and pemphigus foliaceus (PF) are autoimmune diseases in which there is loss of cohesion between keratinocytes (acantholysis) and blistering within the epidermis. PV is characterized by acantholysis predominantly between the epidermal basal cells and suprabasal layers, whereas in PF intraepidermal cleavage is higher in the epidermis. Adhesion between keratinocytes is dependent on the function of transmembrane glycoproteins of the cadherin family present in specialized adhesion junctions, the desmosomes. The pathogenesis of acantholysis In pemphigus is uncertain, but the pemphigus autoantibodies bind to epithelial cadherins. We have used monoclonal antibodies to desmosomal components to investigate their distribution in different forms of pemphigus.Our results show that the localization of desmosomal components is abnormal in intact perilesional epidermis, intact epidermis above the blisters in PV and intact epidermis below the blisters in PF. We suggest that autoantibody binding may have a direct effect on the function of specific epithelial cadherins, but will only cause cell separation where the antigen is the principal adhesion molecule.

Notes: Background  Pili annulati is a rare autosomal dominant inherited hair shaft abnormality in which clinical examination reveals alternating light and dark bands leading to a shiny appearance of the hair. The clinically light bands are the abnormal areas due to cavities within the cortex. The pathogenesis remains unknown.Objectives  To investigate the expression of the basement membrane zone (BMZ) components in pili annulati hair follicles of the scalp.Methods  Transmission electron microscopy (TEM) was carried out on scalp sections of six individuals with pili annulati and six controls. Longitudinal sections of scalp tissues from four individuals with pili annulati and six normal controls were studied by immunohistochemistry with a panel of monoclonal antibodies to the following BMZ components: α6β4 integrin, laminin 5, LH39 antigen, laminin 1, collagen IV and collagen VII.Results  Using TEM, pili annulati scalp specimens exhibited a reduplicated lamina densa in the region of the root bulb in comparison with the single thin electron-dense band in controls. Using immunohistochemistry, there was a wavy BMZ in pili annulati follicles with antibodies to components of the lamina lucida, lamina densa and anchoring fibrils, whereas the BMZ in control hair follicles was as a smooth linear band. The expression of the hemidesmosome-associated α6β4 integrin was linear in both pili annulati and control hair follicles.Conclusions  Our results suggest that the genetic defect may be a mutation in proteins involved in signalling and regulation of formation and degradation of the lamina densa and sublamina densa region resulting in abnormal assembly or remodelling of the BMZ.

Notes: Summary  Background The composition of the basement membrane zone (BMZ) or dermal–epidermal junction in the interfollicular skin has been well documented. However, little is known about the BMZ or connective tissue–epithelial junction along the hair follicle.Objectives  To determine whether the BMZ antigens in the interfollicular epidermis are also present in the BMZ of the anagen hair follicle and to compare whether the expression and distribution of the BMZ components vary between the interfollicular epidermis and the anagen follicle and within different regions of the hair follicle.Methods  Longitudinal cryostat sections of scalp margin specimens from four adult patients undergoing cosmetic surgery, and without known pathology were stained with a panel of monoclonal and polyclonal antibodies to different BMZ constituents using standard indirect immunofluorescence.Results  All the BMZ antigens found in the normal interfollicular epidermis were expressed in the anagen follicle; however, there were regional variations in the intensity and patterns of fluorescence. All the antigens were expressed in a continuous linear pattern along the BMZ of the interfollicular skin, the infundibulum, and the middle part of the hair follicle. Differences were observed in the lower follicle and the hair bulb. There was continuous expression throughout the BMZ of the follicle of laminin-1 and collagen IV, but in contrast, expression of other antigens decreased down the lower follicle. There was weak or even negative staining with antibodies to α6β4 integrin, laminin-5, anchoring filaments, and type VII collagen in the outer aspect of the bulb compared with the hair papilla. In addition, there were special patterns observed along the bilateral middle and lower follicle.Conclusions  Despite the common embryological origin between the interfollicular epidermis and the hair follicle, there is variation in the expression of the BMZ antigens. This may be explained by the histological specialization and functional requirements that reflect the dynamic hair growth cycle.

Notes: The autoimmune blistering disease pemphigus is more common in the Indian subcontinent than in the UK. This study of 19 patients from Oxford, UK and 39 patients from New Delhi, India demonstrates that the incidence of the disease subtypes is different in the two countries, In the UK the commonest subtypes are pemphigus vulgaris and foliaceus with equal prevalence (both eight of 19), but in India pemphigus vulgaris is the must frequent (31 of 39), while pemphigus foliaceus is uncommon (three of 39) and with equal prevalence to the other subtypes. These populations also differ with a younger age at onset in the Indian patients (36.9 India; 52.7 UK) though the sex distribution is the same. Study of the immunopathology shows that the antibodies produced by patients in the two countries do not differ significantly, and arc predominantly of the IgG4 subclass. The antibody produced does not: vary with the subtype of pemphigus or the age or sex of the patient. Although there arc considerable differences between the two groups of patients this difference is not reflected by the subclass of auto-antibody response.