Background & Aims
Neonates are constantly exposed to pain in Intensive Care Units (ICUs) at a critical period of development. Sucrose is used in the management of neonatal pain, however, its long-term effects and repercussions on sensory development and the inflammatory profile constitute a scientific gap. The study aimed to evaluate the effect of sucrose on sensory development and the inflammatory profile in an experimental model of neonatal pain.
Methods
An experimental study was performed, using 38 male (n=20) and female (n=18) Wistar rats that were undergone to the model of neonatal pain based on the rapid insertion of a needle on the lateral and plantar surface of the animal’s hind leg. In the control group, the tip of a cotton swab was used for tactile stimulation. Animals were allocated into four groups: 1) Hyperalgesia + intervention with sucrose (250 g/L; oral administration; n=9); 2) Hyperalgesia + intervention with morphine (10 mg/mL; subcutaneous injection; n=9); 3) Hyperalgesia + intervention with drinking water (oral administration; n=9) and 4) Control (n=11). Paw withdrawal threshold (von Frey filaments), thermal latency (hot plate), muscle strength (grip strenght meter) and gait speed (activity monitor) were assessed at 16, 17, 30, 31, 60, 61, 90 and 91 postnatal days. The analysis of the inflammatory profile (cytokines IL-1?, IL-6, IL-10 and TNF-?) was performed through blood collection on postnatal day 181 (ELISA kits).
Results
Animals treated with sucrose showed a significant increase in paw withdrawal threshold (p?0,005; F=3,009) and thermal threshold (p?0,04; F=2,60) at 15 days when compared to the other groups. There was higher gait speed in the sucrose group (p?0.03; F=2.23) and increased strength in all groups (p=0.001; F=14.61). A shorter thermal latency (p?0,01; F=2,607) was observed on days 62 and 90 in the groups that received water and morphine, respectively, when compared to postnatal day 30. There was no difference between sexes for thermal latency and displacement speed (p?0.09; F?0.695). No significant concentrations of inflammatory cytokines were detected in the blood serum of animals in all groups (p>0.05).
Conclusions
The results confirm the analgesic potential presented by sucrose when administered in the first days of life. Over time, it was not possible to observe superiority between the different treatments used.
References
Sanada, LS et al. Cortex glial cells activation, associated with lowered mechanical thresholds and motor dysfunction, persists into adulthood after neonatal pain. ?Int. J. Dev. Neurosci. 2014;35:(55-63).
Do Carmo, EC et al. Does Pain in the Neonatal Period Influence Motor and Sensory Functions in a Similar Way for Males and Females During Post-Natal Development in Rats?. Pain Med. 2016;17(8):1520-9.
Nuseir KQ et al. Early and late anti nociceptive effects of sucrose on neonatal inflammatory pain in rats: Comparison to a non-steroidal anti-inflammatory drug. Physiol Behav. 2019 Jul 1;206:37-42. doi: 10.1016/j.physbeh.2019.03.014. Epub 2019 Mar 24. PMID: 30917911.
Presenting Author
Isabela Azevedo-Santos
Poster Authors
Topics
- Models: Acute Pain