Expression of bone morphogenetic proteins and their receptors in the normal adult rat spinal cord / 中南大学学报(医学版)

ABSTRACT

Objective To observe the expression distribution of bone morphogenetic proteins (BMP) in the spinal cord of normal adult rats. Methods Expression of BMP2, BMP4, and BMP7, and their receptors BMPR Ⅰa, BMPR Ⅰb, and BMP Ⅱ were detected by immunochemistry analysis in the spinal cord of normal adult rats. Results Expression of BMPR Ia or BMPR Ib was observed in the motor neurons of the anterior horn, sensory neurons of the dorsal horn, oligodentrocytes, some microglia, and some astrocytes. Expression of receptor BMPR Ⅱ was found in the oligodentrocytes and motor neurons in the gray matter of anterior horn. It was also expressed in some glial fibrillary acidic protein (GFAP)-positive astrocytes in the white matter but not in the gray matter. BMP2 and BMP4 were not expressed in the spinal cord of normal adult rats by immunohistochemistry. BMP7 was expressed in all the APC-positive oligodentrocytes, all the NeuN-positive motor neurons in the anterior horn, and some astrocytes in the normal spinal cord. Phosphated pSmad 1/5/8 protein was expressed in all the oligodentrocytes, all the neurons, and some astrocytes, especially in the GFAP-positive astrocytes which were RC2-positive radial glia in the subventricular zone.Conclusion BMP7, BMP receptors, and phosphated pSmad 1/5/8 are expressed in many types of cells whereas BMP2 and BMP4 are not expressed in the spinal cord of normal adult rats, which suggests an important function of BMP signal pathway in the neuron and glia of spinal cord.