Mammalian TRP proteins have been implicated to function as ion channel subunits responsible for agonist-induced Ca 2؉ entry. To date, TRP proteins have been extensively studied by heterologous expression giving rise to diverse channel properties and activation mechanisms including store-operated mechanisms. However, the molecular structure and the functional properties of native TRP channels still remain elusive. Here we analyze the properties of TRP4 (CCE1) channels in their native environment and characterize TRP expression patterns and store-operated calcium currents that are endogenous to bovine adrenal cells. We show by Northern blot analysis, immunoblots, and immunohistochemistry that TRP4 transcripts and TRP4 protein are present in the adrenal cortex but absent in the medulla. Correspondingly, bovine adrenal cortex cells express TRP4 abundantly. The only other TRP transcript found at considerable levels was TRP1, whereas TRP2, TRP3, TRP5(CCE2), and TRP6 were not detectable. Depletion of calcium stores with inositol 1,4,5-trisphosphate or thapsigargin activates store-operated ion channels in adrenal cells. These channels closely resemble calcium release-activated Ca 2؉ (CRAC) channels. Expression of trp4(CCE1) cDNA in antisense orientation significantly reduces both, the endogenous CRAC-like currents and the amount of native TRP4 protein. These results demonstrate that TRP4 contributes essentially to the formation of native CRAC-like channels in adrenal cells.Receptor-operated Ca 2ϩ signaling has been described in a variety of non-excitable cells and has been attributed to basic and specific cell functions like cell growth, differentiation, and hormone release (reviewed by Refs. 1-3). The receptor-dependent and phospholipase C-mediated formation of inositol 1,4,5-trisphosphate (InsP 3 ) 1 leads to the depletion of intracellular Ca 2ϩ stores which in turn activates store-operated Ca 2ϩ channels in the plasma membrane. The mechanisms linking store depletion to channel activation are still unknown but might include direct coupling of store proteins to the plasma membrane channel (1, 4 -7), diffusible messengers (8 -10), or exocytotic insertion of channels preformed in vesicles (11-13). The current picture and implications of these activation mechanism have been reviewed recently (14, 15). The best studied storeoperated Ca 2ϩ channels in terms of function and biophysical properties are calcium release-activated Ca 2ϩ (CRAC) channels which have been originally described in mast cells and T-lymphocytes (16, 17). This prototype of a store-operated Ca 2ϩ channel is characterized by its inward rectifying currents and by its high selectivity for Ca 2ϩ . The molecular structure of CRAC channels, however, remains elusive.Mammalian homologues of the Drosophila TRP and TRPL ion channels are candidate proteins underlying CRAC channels but also other store-operated and/or receptor-operated Ca 2ϩ permeable ion channels. So far, the cDNAs of seven mammalian TRP genes have been cloned and characterized as functional cation c...

The aim of our study was to evaluate the registration accuracy and practicability of a new laser registration technique in comparison to marker registration. From January to August 2001, 36 patients (23 male, 13 female) with brain lesions were operated with navigational guidance. Thirty-five patients were registered by paired-point registration. In 16 patients, a second registration was carried out using a special laser pointer for surface matching (z-touch trade mark, BrainLab, Heimstetten, Germany). Accuracy was evaluated by touching seven anatomic landmarks and a target fiducial with the nonsterile pointer. The distance from the virtual pointer tip to these points was determined on the monitor display (600% zoom). Laser registration is fully retrospective and allows registrations when no markers are applied. z-touch trade mark registration is more sophisticated and time-consuming than marker-based registration (registration time for z-touch trade mark = 7.4 +/- 3.7 min; for markers = 4.1 +/- 1.7 min; p < 0.005). Marker registration proved to be more accurate than z-touch trade mark registration with regard to localization of anatomical landmarks and target fiducials (precision with z-touch trade mark = 2.77 +/- 1.64 mm; with markers = 1.31 +/- 0.87 mm; p < 0.01). Although the registration error was increased and preparation time prolonged with the z-touch trade mark technique, it proved to be a valuable option, especially in children.

Genes related to trp (transient receptor potential) are proposed to encode store‐operated channels. We examined the ionic permeation of recombinant channels formed by stable and transient expression of the TRP homologue bCCE1 in Chinese hamster ovary (CHO) cells (CHO(CCE1)) and rat basophilic leukaemia (RBL) cells, respectively. Store‐operated currents were activated in CHO(CCE1) cells by internal dialysis of IP3 under strong buffering of intracellular Ca2+. The action of IP3 was mimicked by thapsigargin but not by IP4. With extracellular Ca2+, Na+ and Mg2+, the store‐operated currents of CHO(CCE1) rectified inwardly in the presence of internal Cs+. Outward currents were not detected below +80 mV. Identical currents were recorded with external Ba2+ and also with no external Na+ and Mg2+. In the absence of external Mg2+, the inward currents showed an anomalous mole fraction behaviour between Ca2+ and Na+. Half‐maximal inhibition of Na+ currents was observed with ≈100 nM and full block with 2‐5 μM external Ca2+. In the parental CHO(‐) cells, IP3 dialysis evoked inward currents that also displayed anomalous mole fraction behaviour between Ca2+ and Na+. However, half‐maximal block of Na+ currents required 5 times higher Ca2+ concentrations in CHO(‐) cells. Additionally, the density of Ca2+ and Na+ currents at ‐80 mV was 5 and 2 times larger in CHO(CCE1) cells, respectively. In RBL cells, dialysis of IP3 evoked store‐operated currents that showed 1.4‐fold larger densities at ‐80 mV in cells expressing bCCE1. The enhanced density of store‐operated currents in CHO(CCE1) cells and in bCCE1‐transfected RBL cells probably reflects the phenotype of CCE1. These results suggest a highly selective permeation of Ca2+ through recombinant channels formed by CCE1 either alone or in combination with endogenous channel proteins.

Neuron-specific enolase (NSE) and S100B protein have been shown to be increased in cerebrospinal fluid (CSF) and serum of patients suffering from subarachnoid hemorrhage. This study was designed to evaluate the accuracy of NSE and S100B from CSF and serum for the prognosis of outcome and the detection of cerebral infarction, vasospasm and intracranial hypertension. In 55 patients with spontaneous subarachnoid hemorrhage and requiring external ventricular drainage the concentrations of NSE and S100B were determined daily from the serum and the CSF from admission until day 8. At ICU discharge patients' outcome was assessed by the Glasgow outcome scale and occurrence of cerebral infarction, vasospasm and intracranial hypertension were registered. Mean and peak values of each parameter for each patient were calculated. For accuracy assessment receiver operating characteristics were used. Bad outcome (Glasgow outcome scale 1 to 3) was found in 33 patients. Cerebral infarction, vasospasm, and intracranial hypertension were found in 31 (56%), 34 (62%), and 36 (65%) patients. Mean and peak values of NSE CSF (P<0.001), S100B CSF (P<0.001), and S100B serum (P<0.001) but not of NSE serum provided the ability to distinguish between patients with good and bad outcome. The accuracy of NSE CSF and S100B CSF did not differ significantly from that of S100B serum. NSE CSF (P<0.001), S100B CSF (P<0.001), and S100B serum (P<0.001) allowed the detection of cerebral infarction and intracranial hypertension. Cerebral vasospasm was detected by none of the parameters. In conclusion, NSE CSF, S100B CSF, and S100B serum provide similar prognostic values for outcome, intracranial hypertension and cerebral infarction. Significantly lower accuracy was found for NSE serum.