Final answer:
Pruritus, or itch, is related to the activation of µ-opioid receptors through interactions of substances such as endomorphins with various receptors associated with Substance P in the nervous system.
Step-by-step explanation:
The relationship between pruritus (itch) and the activation of μ-opioid receptors involves the effect of specific substances and receptors in the nervous system. Endomorphin-1 and endomorphin-2, which are high-affinity μ-opioid receptor agonists, have been shown to interact differentially with binding sites associated with the neuropeptide Substance P. This interaction suggests a complex modulation where μ-opioid receptor activation could potentially impact the sensation of itching, although the exact mechanisms and their implications in conditions like diabetic painful neuropathy are subjects of ongoing research.