Molecular and neural basis of pleasant touch sensation

Abstract

Pleasant touch provides emotional and psychological support that helps mitigate social isolation and stress. However, the underlying mechanisms remain poorly understood. Using a pleasant touch–conditioned place preference (PT-CPP) test, we show that genetic ablation of spinal excitatory interneurons expressing prokineticin receptor 2 (PROKR2), or its ligand PROK2 in sensory neurons, abolishes PT-CPP without impairing pain and itch behaviors in mice. Mutant mice display profound impairments in stress response and prosocial behaviors. Moreover, PROKR2 neurons respond most vigorously to gentle stroking and encode reward value. Collectively, we identify PROK2 as a long-sought neuropeptide that encodes and transmits pleasant touch to spinal PROKR2 neurons. These findings may have important implications for elucidating mechanisms by which pleasant touch deprivation contributes to social avoidance behavior and mental disorders.

Effectiveness and functional magnetic resonance imaging outcomes of Tuina therapy in patients with post-stroke depression: A randomized controlled trial

“…However, the results of some animal studies have shown that the analgesic mechanism of Tuina may be related to the inhibition of the upward conduction of pain by stimulating receptors on the skin ( 33 , 34 ). Recently, some high-quality research showed that the molecular and neural mechanisms by which a pleasant touch similar to the Tuina effect can reduce stress may be related to the PROK2 neuropeptide encoding pathway and transmission to PROKR2 neurons in the spinal cord ( 35 ).…”

Sensation of pleasant touch: from molecules to circuits and behaviours

“…identified a crucial role of the PROK2-PROKR2 signalling within the spinal circuit in pleasant touch sensation (Fig. 1 ), providing the first evidence for the molecular and neural basis of how pleasant touch information is encoded and integrated from the skin to the spinal cord and highlighting the important role of neuropeptides in the processing of somatosensory information 1 (Fig. 1 ).…”

“…Modified from the highlighted paper. 1 HC stroking, homecage stroking; Pre-c BL, preconditioning baseline; Pref T, preference test. b Main experiments and findings from the highlighted paper.…”

“…b Main experiments and findings from the highlighted paper. 1 c Diagrams of touch signalling from the skin to spinal cord and brain in recent studies 1 – 3 …”

“… 4 , 5 Interestingly, Liu et al found that a previously uncharacterized subpopulation in the laminae II of the spinal cord that uniquely expresses prokineticin receptor 2 (PROKR2). 1 …”