Brain region-specific regulation of urocortin 1 innervation and corticotropin-releasing factor receptor type 2 binding by ethanol exposure.
BACKGROUND
Ethanol administration and consumption selectively activates the urocortin 1 (Ucn1)-expressing neurons of the Edinger-Westphal nucleus. We investigated whether repeated ethanol exposure affects Ucn1 and Ucn1-responsive corticotropin-releasing factor type-2 receptors (CRF2).


METHODS
Male C57BL/6J and DBA/2J mice were exposed to 2 g/kg ethanol via intraperitoneal injection once per day for 14, seven, or zero days. Ucn1 immunoreactivity was measured in the lateral septum, dorsal raphe, and Edinger-Westphal nucleus. In a separate experiment, C57BL/6J mice were exposed to ethanol for seven, one, or zero days, and CRF2 receptor binding was measured in the lateral septum and dorsal raphe by receptor autoradiography.


RESULTS
Ethanol exposure induced parallel changes in Ucn1 immunoreactive terminal fibers in the lateral septum and dorsal raphe of both strains. Seven ethanol exposures but not one ethanol exposure significantly increased CRF2 receptor binding in the dorsal raphe and slightly increased CRF2 receptor binding in the lateral septum.


CONCLUSIONS
These results provide evidence that the Ucn1/CRF2 receptor system can be modified by ethanol exposure. They additionally suggest that this system may be involved in behavioral changes during alcoholism.
Weitemier
Adam Z
AZ
Department of Behavioral Neuroscience, Oregon Health and Science University and Portland Alcohol Research Center, Portland, Oregon 97239, USA. weitemie@ohsu.edu
Ryabinin
Andrey E
AE
D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects; D001921:Brain / Q000187:drug effects* / Q000378:metabolism; D003346:Corticotropin-Releasing Hormone / Q000032:analysis*; D000431:Ethanol / Q000494:pharmacology*; D007150:Immunohistochemistry; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008811:Mice, Inbred DBA; D009474:Neurons / Q000737:chemistry*; D018019:Receptors, Corticotropin-Releasing Hormone / Q000032:analysis* / Q000378:metabolism; D013045:Species Specificity; D054832:Urocortins
C101531:CRF receptor type 2; D018019:Receptors, Corticotropin-Releasing Hormone; D054832:Urocortins; D000431:Ethanol; D003346:Corticotropin-Releasing Hormone