Photo Credit: Magic Mine
The following is a summary of “Pain perception during baroreceptor unloading by lower body negative pressure,” published in the April 2024 issue of Pain by Neumann et al.
Blood pressure (BP) hypoalgesia is when people with high blood pressure feel less pain. It is likely due to changes in baroreceptor sensitivity. However, baroreceptor stimulation can also raise blood pressure, affecting pain sensitivity.
Researchers conducted a retrospective study exploring the role of baroreceptor activity in BP-related pain reduction.
They used 20 healthy volunteers to understand pain perception by using thermal forearm stimulation during baroreceptor unloading via lower body negative pressure (LBNP) at -5 and -20 mmHg. The BP and heart rate were monitored continuously. The sequence of LBNP stimulation was counterbalanced.
The results showed that the heart rate increased to -20 mmHg LBNP, not at -5 mmHg. However, neither changed blood pressure. Sensory thresholds and pain perception stayed the same during LBNP, including responses to thermal heat stimulus.
Investigators concluded that reducing baroreceptor activity without changing BP did not affect pain perception, with no correlation between baroreflex and pain sensitivity.
Source: onlinelibrary.wiley.com/doi/full/10.1002/ejp.2273
