TY - JOUR
T1 - Urocortinergic neurons respond in a differentiated manner to various acute stressors in the Edinger-Westphal nucleus in the rat
AU - Gaszner, Balázs
AU - Csernus, Valér
AU - Kozicz, Tamás
PY - 2004/12/6
Y1 - 2004/12/6
N2 - Corticotropin-releasing factor (CRF) was implicated as being a major contributor to the neurochemically mediated central regulation of stress response; however, an increasing body of evidence suggests that, besides CRF, other members of this neuropeptide family, such as urocortin (Ucn), may also play a role in modifying the efferent components of immune, endocrine, and behavioral responses to stress. Ucn's distribution in the rat brain has been demonstrated, with the most abundant Ucn-immunoreactive perikarya present in the Edinger-Westphal nucleus (E-WN). Acute pain and immobilization stresses recruit E-WN neurons, however, the activation pattern of E-WN Ucn neurons in response to various acute systemic and neurogenic challenges has not been compared in a single study. We therefore combined quantitative Fos imaging as a marker for neuronal activation with urocortin immunohistochemistry to visualize neurons induced by intravenous lipopolysaccharide (LPS; 100 μg/kg), ether inhalation, restraint, hyperosmotic (1.5 M NaCl i.p.), and hypotensive hemorrhage challenges. Neurons in the E-WN responded with the strongest Fos induction to LPS, but ether and restraint stress also resulted in massive Fos immunoreactivity 2 hours after stress. Unexpectedly, hyperosmotic and hypotensive hemorrhage stresses did not induce urocortinergic perikarya in this brain area 2 hours poststress. This challenge-specific recruitment of E-WN neurons was independent of stress-induced adrenal response. The biological significance and the stress-specific activation of E-WN urocortinergic neurons will be discussed.
AB - Corticotropin-releasing factor (CRF) was implicated as being a major contributor to the neurochemically mediated central regulation of stress response; however, an increasing body of evidence suggests that, besides CRF, other members of this neuropeptide family, such as urocortin (Ucn), may also play a role in modifying the efferent components of immune, endocrine, and behavioral responses to stress. Ucn's distribution in the rat brain has been demonstrated, with the most abundant Ucn-immunoreactive perikarya present in the Edinger-Westphal nucleus (E-WN). Acute pain and immobilization stresses recruit E-WN neurons, however, the activation pattern of E-WN Ucn neurons in response to various acute systemic and neurogenic challenges has not been compared in a single study. We therefore combined quantitative Fos imaging as a marker for neuronal activation with urocortin immunohistochemistry to visualize neurons induced by intravenous lipopolysaccharide (LPS; 100 μg/kg), ether inhalation, restraint, hyperosmotic (1.5 M NaCl i.p.), and hypotensive hemorrhage challenges. Neurons in the E-WN responded with the strongest Fos induction to LPS, but ether and restraint stress also resulted in massive Fos immunoreactivity 2 hours after stress. Unexpectedly, hyperosmotic and hypotensive hemorrhage stresses did not induce urocortinergic perikarya in this brain area 2 hours poststress. This challenge-specific recruitment of E-WN neurons was independent of stress-induced adrenal response. The biological significance and the stress-specific activation of E-WN urocortinergic neurons will be discussed.
KW - Immediate early genes
KW - Immunohistochemistry
KW - Neurogenic stress
KW - Systemic stress
KW - Urocortin
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U2 - 10.1002/cne.20343
DO - 10.1002/cne.20343
M3 - Article
C2 - 15514930
AN - SCOPUS:8844255454
SN - 0021-9967
VL - 480
SP - 170
EP - 179
JO - Journal of Comparative Neurology
JF - Journal of Comparative Neurology
IS - 2
ER -