Immunohistochemical detection of phosphorylated form of extracellular signal-regulated kinase 1/2 in rat vestibular nuclei following hemorrhagic hypotension.
The purpose of this study was to evaluate the expression of the phosphorylated form of extracellular-regulated protein kinase 1/2 (pERK1/2), which is one of the major regulatory factors for transcription of the c-fos oncogene in neurons, within the vestibular nuclei (VN) of rats following acute arterial hypotension. Following acute arterial hypotension induced by rapid hemorrhage, a significant number of pERK1/2-immunoreactive neurons appeared bilaterally in the caudal aspect of the medial and inferior VN. No labeling of pERK1/2 was observed in the lateral VN. The peak expression of pERK1/2-immunoreactive neurons in these nuclei occurred within 5 min after hemorrhage. In bilaterally labyrinthectomized rats, the appearance of pERK1/2-immunoreactive neurons was eliminated in the VN. These results suggest that, following acute hypotension, afferent signals from the peripheral vestibular receptors are required for activation of extracellular signal-regulated kinase 1/2 in the VN.
Kim
Min Sun
MS
Department of Physiology, Wonkwang University School of Medicine and Vestibulocochlear Research Center at Wonkwang University, Iksan 570-749, South Korea.
Choi
Dong Ok
DO
Choi
Myoung Ae
MA
Kim
Jae Hyo
JH
Kim
Kwang Yong
KY
Lee
Moon Young
MY
Rhee
Jeong Kun
JK
Chun
Sang Woo
SW
Park
Byung Rim
BR
D000818:Animals; D004789:Enzyme Activation / Q000502:physiology; D006470:Hemorrhage / Q000201:enzymology*; D007022:Hypotension / Q000201:enzymology*; D019950:Mitogen-Activated Protein Kinase 1 / Q000032:analysis / Q000096:biosynthesis*; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases / Q000032:analysis / Q000096:biosynthesis; D010766:Phosphorylation; D051381:Rats; D017207:Rats, Sprague-Dawley; D014726:Vestibular Nuclei / Q000737:chemistry / Q000201:enzymology*
D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases