EFFECT OF LEAD ON PAIN SENSITIVITY USING THE FORMALIN INDUCED PAW LICKING TEST MODEL

The impact of lead exposure on pain sensitivity is a significant concern due to its potential to alter neurological and sensory functions. This study investigates the effects of lead exposure on pain sensitivity in male Wistar rats using the formalin-induced paw licking test, a well-established method for assessing pain responses in rodents. The formalin test involves injecting a small amount of formalin into the paw, which causes a biphasic pain response characterized by an initial acute phase followed by a prolonged inflammatory phase. Lead, a neurotoxic heavy metal, has been shown to interfere with various physiological processes, including the central and peripheral nervous systems. Recent studies have indicated that lead exposure may alter pain perception, but the mechanisms remain unclear (Journal of Pain Research, 10, 1275-1291). In this study, male Wistar rats were exposed to lead acetate through their drinking water for a period of four weeks to simulate chronic exposure. Following lead exposure, the formalin-induced paw licking test was conducted to evaluate changes in pain sensitivity. The findings of this study provide valuable insights into the neurotoxic effects of lead on pain sensitivity, highlighting the potential for lead to exacerbate pain conditions through multiple pathways. These results underscore the need for further research to fully elucidate the mechanisms by which lead alters pain perception and to explore potential therapeutic interventions for mitigating lead-induced pain hypersensitivity. The formalin-induced paw licking test serves as a robust model for studying these effects, offering a comprehensive approach to understanding the complex interplay between environmental toxins and pain regulation in the nervous system.