Psychosomatic complaints and unwinding of sympathoadrenal activation after work

It is well known that chronically elevated catecholamine excretion rates are associated with health problems, indicating the importance of recovery after work. In 28 male truck drivers, unwinding after work was found to be insufficient. The resulting spillover of sympathoadrenal activation, as assessed by urinary excretion rate of adrenaline and noradrenaline, was significantly related to self-reported psychosomatic health complaints. Age had a significant effect on spillover of noradrenaline, whereas this personal factor was only marginally significant for adrenaline. This study shows that elevated sympathoadrenal activation after work, and not only increased reactivity during work, causes health problems, although it is also plausible that young and healthy drivers are able to unwind more quickly than older drivers with psychosomatic complaints. (C) 1998 John Wiley & Sons, Ltd

Probing the interaction of lipids with the non-annular binding sites of the potassium channel KcsA by magic-angle spinning NMR

The activity of the potassium channel, KcsA is tightly regulated through the interactions of anionic lipids with high-affinity non-annular lipid binding sites located at the interface between the channel's subunits. Here we present solid-state phosphorous NMR studies that resolve the negatively charged lipid phosphatidylglycerol within the non-annular lipid-binding site. Perturbations in chemical shift observed upon the binding of phosphatidylglycerol are indicative of the interaction of positively charged sidechains within the non-annular binding site and the negatively charged lipid headgroup. Site directed mutagenesis studies have attributed these charge interactions to R64 and R89. Functionally the removal of the positive charges from R64 and R89 appears to act synergistically to reduce the probability of channel openin