Biology subjects

Pimpinella, S.

Publications and source records attributed to Pimpinella, S..

2 recordsLinked to original sources

bioRxiv2025

Age-related sensory dysfunction reconfigures the spinal circuitry for touch, itch and pain

Sensory dysfunction during aging results in sharp increases in the incidence of chronic itch and pain, which counterintuitively are associated with reduced sensitivity to light touch. While age-related changes in peripheral mechanosensory transmission have been described, the contribution central mechanisms make to altered itch and pain responses remains largely unknown. Here, we show that signalling from cutaneous touch receptors is essential for maintaining the cellular composition of the central somatosensory circuits that process itch and pain information in adult mice. In particular, the loss of excitatory signalling from Merkel cells during aging causes the degeneration of subsets of molecularly defined inhibitory and excitatory neurons in the dorsal spinal cord, including inhibitory neurons that express the neuropeptide NPY. Our demonstration that the activity-dependent loss of inhibitory NPY neurons drives itch and pain hypersensitivity in old animals reveals the mechanism by which aging reconfigures the central neuronal circuits that sense touch, itch and pain.

neuroscience↗

bioRxiv2021

Rabies anterograde monosynaptic tracing reveals organization of spinal sensory circuits

Somatosensory neurons detect vital information about the environment and internal status of the body, such as temperature, touch, itch and proprioception. The circuit mechanisms controlling the coding of somatosensory information and the generation of appropriate behavioral responses are not clear yet. In order to address this issue, it is important to define the precise connectivity patterns between primary sensory afferents dedicated to the detection of different stimuli and recipient neurons in the central nervous system. In this study we used a rabies tracing approach for mapping spinal circuits receiving sensory input from distinct, genetically defined, modalities. We analyzed the anatomical organization of spinal circuits involved in coding of thermal and mechanical stimuli and showed that somatosensory information from distinct modalities is relayed to partially overlapping ensembles of interneurons displaying stereotyped laminar organization, thus highlighting the importance of positional features and population coding for the processing and integration of somatosensory information.

neuroscience↗