Identification of coffee components that stimulate dopamine release from pheochromocytoma cells (PC-12).

Coffee and caffeine are known to affect the limbic system, but data on the influence of coffee and coffee constituents on neurotransmitter release is limited. We investigated dopamine release and Ca(2+)-mobilization in pheochromocytoma cells (PC-12 cells) after stimulation with two lyophilized coffee beverages prepared from either Coffea arabica (AR) or Coffea canephora var. robusta (RB) beans and constituents thereof. Both coffee lyophilizates showed effects in dilutions between 1:100 and 1:10,000. To identify the active coffee compound, coffee constituents were tested in beverage and plasma representative concentrations. Caffeine, trigonelline, N-methylpyridinium, chlorogenic acid, catechol, pyrogallol and 5-hydroxytryptamides increased calcium signaling and dopamine release, although with different efficacies. While N-methylpyridinium stimulated the Ca(2+)-mobilization most potently (EC(200): 0.14±0.29µM), treatment of the cells with pyrogallol (EC(200): 48±14nM) or 5-hydroxytryptamides (EC(200): 10±3nM) lead to the most pronounced effect on dopamine release. In contrast, no effect was seen for the reconstituted biomimetic mixture. We therefore conclude that each of the coffee constituents tested stimulated the dopamine release in PC-12 cells. Since no effect was found for their biomimetic mixture, we hypothesize other coffee constituents being responsible for the dopamine release demonstrated for AR and RB coffee brews.

[The value of thoracoscopy in thorax trauma]. / Hat die Thorakoskopie beim Thoraxtrauma einen Platz?

A hemodynamically stable patient presenting with persistent bleeding through his chest tube (ICD) is a classic indication for early thoracoscopic intervention in trauma. The source of bleeding and air leaks can be identified and often treated: bleeding and perforated pulmonary segments can be resected, and chest wall bleeding may be coagulated or sutured. Injuries to the diaphragm are difficult to diagnose, as they might not be seen in conventional trauma imaging without gross herniation of intra-abdominal contents into the thoracic cavity. Identifying the site of diaphragm perforation can give useful hints in thoracoabdominal trauma, identifying injured cavities and localizing the bullet or stab tract. Most often, diaphragmatic defects may be closed during diagnostic thoracoscopy as well. Non- or partially drainable hemothorax is another indication for thoracoscopy. Coagulated blood can be mechanically mobilised, and aspirated or primary bleeding may be stopped. Effective lavage and a high-performance suction device are required. Correct placement of the drainage is part of optimized therapy, along with inspection of all intrathoracic organs and surfaces. Furthermore, surgical and anaesthesiological teamwork and experience are prerequisites for the fast, professional application of a minimally invasive thoracoscopic approach in chest trauma patients. Diagnostically and theurapeutically, thoracoscopy plays an important role in the trauma setting--in the case of hemodynamically stable patients.