Co-localization of vasoactive intestinal polypeptide, γ-aminobutyric acid and choline acetyltransferase in neocortical interneurons of the adult rat

Interneurons immunoreactive for vasoactive intestinal polypeptide (VIP) are integral elements of columnar organization patterns in the rat cerebral cortex. By application of the sensitive mirror technique, the co-localization of VIP with the classical inhibitory neurotransmitter γ-aminobutyric acid (GABA) and the acetylcholine-synthesizing enzyme, choline acetyltransferase (ChAT), was investigated in neocortical neurons. Furthermore, the frequency of co-localization of ChAT with GABA was determined. In a sample of 118 VIP-immunoreactive neurons, mostly from the primary somatosensory cortex, it was demonstrated that virtually all of them reveal immunoreactivity for GABA and, therefore, are to be GABAergic. Moreover, 34% of mostly bipolar, VIP-positive neurons contained ChAT and are, thus, supposedly cholinergic as well. Co-localization of VIP and ChAT varied according to cortical laminae. Finally, 88% of a total of 60 ChAT-immunoreactive neurons were also immunostained for GABA. It is concluded that almost all VIP-immunoreactive neurons and most of the cholinergic neurons in rat neocortex represent partly overlapping subpopulations of inhibitory interneurons utilizing GABA.     

Vascular Endothelial Growth Factor Expression and Cyclosporine Toxicity in Renal Allograft Rejection

The aim of this study was to evaluate the influence of vascular endothelial growth factor (VEGF) on renal function and on development of interstitial fibrosis (IF) in renal allografts. Tubular and interstitial expressions of VEGF and TNF-α, and density of macrophages in the interstitium were examined in 92 patients with nonrejected kidneys, acute rejection (AR), chronic allograft nephropathy (CAN), borderline changes (BC) and acute cyclosporin A (CsA) toxicity. Follow-up biopsy specimens from patients with AR and BC were evaluated for development of IF. A significant difference in tubular and interstitial VEGF expressions was found between patients with AR, BC, CAN and CsA toxicity (p < 0.001). Macrophage infiltration was positively correlated with VEGF and TNF-α expressions (p < 0.001). VEGF expression increased with increasing expression of TNF-α (p < 0.001). Renal function in first 6 months after initial biopsy was better in patients with marked tubular VEGF expression (p < 0.01); however, in follow-up, development of IF and graft loss was found earlier in these patients (p < 0.01 and p < 0.05, respectively). Increased renal VEGF expression has protective properties immediately following renal allograft but allows for increased risk of early IF, and therefore poor graft outcome in the long term.     

Iatrogenic injuries to ureter, bladder and urethra during abdominal and pelvic operations

Abdominal and pelvic operations at Departments of Obstetrics and Gynaecology, and General Surgery play an important role in ureteral, bladder and rarely urethral injuries. Fifty-nine patients with iatrogenic ureteral, bladder and urethral injuries were treated at the Department of Urology, Atatürk University Research Hospital, between 1985 and 1995. These injuries were urinary vaginal fistulas in 43 patients (vesicovaginal 33, ureterovaginal 7, urethrovaginal 2 and vesicovaginal plus urethrovaginal 1), ureteric ligation in 9, bladder laceration in 7. These injuries were treated by different methods. All patients were followed up by intravenous urography (IVU) and urine culture three months later. It must be borne in mind that iatrogenic urinary tract injuries are not rare. Bladder and ureteral catheterization must be performed to prevent these complications.     

Neurons immunoreactive for vasoactive intestinal polypeptide in the rat primary somatosensory cortex: morphology and spatial relationship to barrel-related columns

Vasoactive intestinal polypeptide (VIP) in neocortex affects neuronal excitability as well as cortical blood flow and metabolism. Interneurons immunoreactive for VIP (VIP-IR neurons) are characterized by their predominantly bipolar appearance and the radial orientation of their main dendrites. In order to determine whether the morphology of VIP-IR neurons is related to the functional organization of the cortex into vertical columns, we combined both immunostaining of neurons containing VIP and cytochrome oxidase histochemistry for visualizing barrels, morphological layer IV correlates of functional columns, in the primary somatosensory (barrel) cortex of rats. VIP-IR neurons were localized in supragranular (48%), granular (16%), and infragranular layers (36%) as well as in the white matter. In the granular layer, a clear trend that more neurons were located in interbarrel septa rather than in barrels could be observed, resulting in a neuronal density which was about one-third higher in the septal area. VIP-IR neurons from the different cortical layers were three-dimensionally reconstructed from serial sections by using a computer microscope system. The neurons were mostly bipolar. Striking morphological differences in both axonal and dendritic trees were found between neurons whose cell bodies were located in supragranular, granular, and the upper part of infragranular layers, and those whose cell bodies were located in the area below. The former had dendrites which often reached layer I, where they bifurcated several times, and axonal trees which were particularly oriented vertically, with a tangential extent smaller than the width of barrels. Therefore, these neurons were mostly confined to either a barrel- or septum-related column. By contrast, the dendrites of neurons of the latter group did not reach the granular layer. Furthermore, these neurons had axons with sometimes very long horizontal collaterals, which often spanned two, in one case three, barrel columns. It is proposed that the differential morphology of neurons with different locations as stated above parallels to some extent the divergence of input streaming into the corresponding layer-defined areas. As a possible consequence of this, VIP-IR neurons may be capable of adapting the excitability and metabolism of cortical compartments either in a spatially limited or more extensive way.     

Autoimmune estrogen dermatitis in an infertile female

Autoimmune estrogen dermatitis is a cyclical cutaneous eruption that occurs premenstrually and goes to the rapid resolution within a few days of menstrual cycles. The disorder has variable clinical manifestations consisting of macules, papules, vesicles, urticarial lesions, bullae, eczematous plaques, and erythema multiforme-like lesions. Herein, we present a case of a 30-year-old woman with attacks of edema and erosions involving the oral and genital mucosal sites on every first day of her menstruation period. She had also multiple endocrinological problems such as hypotroidism and infertility. To determine the sex hormon sensitivity, intradermal skin tests were performed. Based on her personal history and skin test findings, a diagnosis of autoimmune estrogen dermatitis was made. After the oophorectomy, she was free from the skin and mucosal symptoms. We propose that it is important to suspect the diagnosis of autoimmune estrogen dermatitis in patients who present with recurrent cylic eruptions and it must be kept in mind that these patients might have a concomitant infertility.