EFFECTS OF PREVIOUS EXERCISE TRAINING ON PLASMA AND TISSUE NITRITE, AND CARDIOVASCULAR PARAMETERS IN RATS WITH PARKINSONISM INDUCED BY 6‐OHDA

Abstract

In Parkinson's disease (PD) in addition to motor symptoms, presents cardiovascular dysfunctions, such as postural hypotension and blood pressure lability. Studies have shown that physical exercise decreases the risk of developing PD, as well as slows its progression. During aerobic training, there is an increase in the peripheral production of nitric oxide (NO), as well as in then substantia nigra pars compacta (SNpc) of patients with PD. However, no study evaluating the effects of exercise on NO levels of PD and the alterations on mean arterial pressure (MAP) and heart rate (HR) after inhibition of NO synthase (NOS) by Nw‐nitro‐arginine‐methyl‐ester (L‐NAME) in animals submitted to prior physical training and induced parkinsonism with 6‐hydroxydopamine (6‐OHDA) have been performed. Trained (T) or sedentary (S) animals underwent stereotactic surgery for bilateral 6‐OHDA or vehicle microinfusion (Sham group) in the SNPc. After 6 days, the animals were catheterized (artery and vein) to record the baseline parameters, followed by inhibition of NOS by L‐NAME (10mg/kg). A nitrite dosage was performed in the aorta, heart and plasma. After 4 weeks of swimming, there was resting bradycardia in the trained groups (6‐OHDA T and Sham T) (p <0.05). There was no difference in the NO from plasma in the four groups. In the aorta, there was an increase of NO in the 6‐OHDA group (p <0.05) when compared to Sham S, and a decrease in 6‐OHDA T animals (p <0.05) when compared to 6‐OHDA S and Sham T. At the heart, there was an increase in NO in the Sham T in relation to the sedentary ones and a decrease of NO in the animals 6‐OHDA T in relation to Sham T (p <0.05). Administration of L‐NAME promoted an increase in MAP and a decrease in HR in all groups, presenting lower increases in MAP in 6‐OHDA animals. In the FC, the difference between groups was a consequence of physical training. The data suggest the involvement of different NOS isoforms on cardiovascular system activated after physical training and Parkinsonism by 6‐OHDA.Support or Funding InformationCapes (fellowship to Lorena de Jager)CNPq (Research fellowships to MCMP, CCC, and PPF)This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.