Endurance after propranolol in the human execution of a general dynamic exercise

The effects of a single oral dose of 40 mg propranolol on endurance time and on the maximum oxygen consumption were studied in eight healthy young men. They were running on a motor-driven treadmill (work rate from 80 to 150% VO2 max. The VO2 max and endurance time were decreased to an average of 10 and 30% of controls respectively. The relationship between the endurance time and the relative work load (VO2/VO2 max) remained unchanged after beta-adrenoceptor blockade. The reduction of the endurance time following beta-adrenoceptor blockade is a consequence of the reduction of the VO2 max

Disruption of endocytosis through chemical inhibition of clathrin heavy chain function

Clathrin mediated endocytosis CME is a highly conserved and essential cellular process in eukaryotic cells, but its dynamic and vital nature makes it challenging to study using classical genetics tools. In contrast, although small molecules can acutely and reversibly perturb CME, the few chemical CME inhibitors that have been applied to plants are either ineffective or show undesirable side effects. Here, we identify the previously described endosidin9 ES9 as an inhibitor of clathrin heavy chain CHC function in both Arabidopsis and human cells through affinity based target isolation, in vitro binding studies and X ray crystallography. Moreover, we present a chemically improved ES9 analog, ES9 17, which lacks the undesirable side effects of ES9 while retaining the ability to target CHC. ES9 and ES9 17 have expanded the chemical toolbox used to probe CHC function, and present chemical scaffolds for further design of more specific and potent CHC inhibitors across different system