TY - JOUR

T1 - Intraspinal stretch receptor neurons mediate different motor responses along the body in lamprey

AU - Hsu, Li-Ju

AU - Zelenin, Pavel V

AU - Grillner, Sten

AU - Orlovsky, Grigori N

AU - Deliagina, Tatiana G

N1 - Copyright © 2013 Wiley Periodicals, Inc.

PY - 2013/11

Y1 - 2013/11

N2 - In lampreys, stretch receptor neurons (SRNs) are located at the margins of the spinal cord and activated by longitudinal stretch in that area caused by body bending. The aim of this study was a comprehensive analysis of motor responses to bending of the lamprey body in different planes and at different rostrocaudal levels. For this purpose, in vitro preparation of the spinal cord isolated together with notochord was used, and responses to bending were recorded from SRNs, as well as from motoneurons innervating the dorsal (dMNs) and ventral (vMNs) parts of a myotome. It was found that SRNs were activated on the convex (stretched) side of the preparation during bending both in the yaw and in the pitch plane. By contrast, responses of motoneurons depended on the site and plane of bending. In the yaw plane, concave responses to bending of rostral segments and convex responses to bending of mid-body segments prevailed. In the pitch plane, convex responses in dMNs and concave responses in vMNs to bending in mid-body segments prevailed. These spinal reflexes could contribute to feedback regulation of locomotor body undulations and to the control of body configuration during locomotion. After a longitudinal split of the spinal cord, only convex responses in motoneurons were present, suggesting an important role of contralateral networks in determining the type of motor response. Stimulation of the brainstem changed the type of motor response to bending, suggesting that these spinal reflexes can be modified by supraspinal signals in accordance with different motor behaviors.

AB - In lampreys, stretch receptor neurons (SRNs) are located at the margins of the spinal cord and activated by longitudinal stretch in that area caused by body bending. The aim of this study was a comprehensive analysis of motor responses to bending of the lamprey body in different planes and at different rostrocaudal levels. For this purpose, in vitro preparation of the spinal cord isolated together with notochord was used, and responses to bending were recorded from SRNs, as well as from motoneurons innervating the dorsal (dMNs) and ventral (vMNs) parts of a myotome. It was found that SRNs were activated on the convex (stretched) side of the preparation during bending both in the yaw and in the pitch plane. By contrast, responses of motoneurons depended on the site and plane of bending. In the yaw plane, concave responses to bending of rostral segments and convex responses to bending of mid-body segments prevailed. In the pitch plane, convex responses in dMNs and concave responses in vMNs to bending in mid-body segments prevailed. These spinal reflexes could contribute to feedback regulation of locomotor body undulations and to the control of body configuration during locomotion. After a longitudinal split of the spinal cord, only convex responses in motoneurons were present, suggesting an important role of contralateral networks in determining the type of motor response. Stimulation of the brainstem changed the type of motor response to bending, suggesting that these spinal reflexes can be modified by supraspinal signals in accordance with different motor behaviors.

KW - Animals

KW - Brain Stem/physiology

KW - Calcium/metabolism

KW - Functional Laterality

KW - In Vitro Techniques

KW - Lampreys

KW - Mechanoreceptors/physiology

KW - Motor Neurons/physiology

KW - Physical Stimulation

KW - Reflex/physiology

KW - Spinal Cord/cytology

U2 - 10.1002/cne.23382

DO - 10.1002/cne.23382

M3 - Journal article

C2 - 23749436

VL - 521

SP - 3847

EP - 3862

JO - The Journal of Comparative Neurology

JF - The Journal of Comparative Neurology

SN - 0021-9967

IS - 16

ER -