Putative Effects of Lead on the Endocannabinoid System: A Literature Review and Summary

Lead is a naturally occurring metal found in numerous compounds used in everyday life. Toxicity from lead is a well-known public health problem. Its effects are implicated in multiple tissues, encompassing the gastrointestinal, renal, cardiovascular, and neurological systems. Endocannabinoid receptors are involved in each of these systems, but the effects of lead on the receptors themselves are not well elucidated. In the neurological system, lead has varying interactions with neurotransmitters and downstream regulators implicated in neuronal transmissions influenced by endocannabinoid receptor function. Lead's effect is likely indirect on endocannabinoid receptor function; however, its influence on neuronal function is likely inhibitory to the receptor's functioning. Lead has also been implicated in oxidative stress states, which would influence endocannabinoid receptors' function. The literature clearly supports lead having a negative impact on the overall function of endocannabinoid receptors, setting the stage for pathological states related to diminished neurosynaptic function and, in embryology, altered neuronal development, especially of the neural tube.