Vascular endothelial growth factor expression in heart of rats exposed to hypobaric hypoxia: differential response between mRNA and protein.

This study investigated the role of vascular endothelial growth factor (VEGF) in the neoangiogenesis induced in heart in response to hypoxia. The time-course of adaptive changes in capillary supply, expression of VEGF mRNA and protein was studied in right (RV) and left ventricles (LV) of rats exposed to hypobaric hypoxia during 1-25 days (barometric pressure = 505 hPa). VEGF mRNA levels encoding for VEGF 188 and 164 isoforms were measured by reverse transcription-polymerase chain reaction (RT-PCR) and VEGF protein was determined by Western blotting.

Over-stimulation of the vestibular system and body balance.

The purpose of this study was to examine whether an over-stimulation of the vestibular system, induced by thousands of time saccadic head stimulations, affects the vestibular sensitivity, and consequently if such a phenomenon could contribute to the deterioration of postural stability observed after a long distance running exercise. Eighteen athletic subjects performed a 20.5 km over ground race with an average speed of 15 km x h(-1), corresponding roughly to 7,500 strides shocks with associated saccadic accelerations transmitted to the head.

Exercise-induced expression of vascular endothelial growth factor mRNA in rat skeletal muscle is dependent on fibre type.

In this study, we quantified the expression of the vascular endothelial growth factor (VEGF) gene in individual muscle fibres at the end of a single 90 min run of 20-25 m min-1, at 10 % incline. In addition, we evaluated the co-ordinated expression of several hypoxia-sensitive genes, including the ORP-150 gene. Individual fibres were taken from rat plantaris muscle, either at the end of a single bout of exercise or at rest, and classified as Type I, IIa, IIx or IIb, according to the expression of myosin heavy chain (MHC) isoforms.