Exercise Training Lowers the Enhanced Tonically Active Glutamatergic Input to the Rostral Ventrolateral Medulla in Hypertensive Rats

The authors tested how low intensity exercise affects the glutamatergic input to the RVLM in spontaneously hypertenive rats. They used WKY and SHR and trained them in treadmill for a period of 12 weeks. Citrate synthase concentration was measured as a measure of exercise training efficacy.  Microinjections were performed in the RVLM to study the changes in BP, HR and RSNA. Blood pressure for the time course experiment were performed using tail-cuff method. Western blotting was performed in RVLM punches to detect the changes in protein levels of vesicular glutamate transporter 2 (vGLUT2). High-performance liquid chromatography (HPLC) was used to measure the glutamate concentration. Data was analysed by a two-way ANOVA followed by post hoc with Student Newman-Keuls. Exercise training decreased the baseline BP and RSNA in SHRs. Execrise training attenuated the decrease in BP, HR and RSNA evoked by blockade of glutamate receptors in the RVLM of SHRs. Exercise training in the SHRs decreased the concentration of glutamate and protein expression of vGLUT2. The overall conclusion is that exercise training lowers the tonically active gluamatergic input in the RVLM of SHRs.

-Madhan