Immunohistochemical localization of corticotropin-releasing factor in the brain and corticotropin-releasing factor and thyrotropin-stimulating hormone in the pituitary of chinook salmon (Oncorhynchus tshawytscha).
This report describes the distribution of corticotropin-releasing factor (CRF)-like immunoreactivity in the brain and the contiguous localization of CRF- and thyrotropin-stimulating hormone (TSH)-like immunoreactivity in the pituitary of hatchery-reared, juvenile chinook salmon (Oncorhynchus tshawytscha). Results show that CRF-immunoreactive cell bodies exist in the parvocellular and magnocellular nuclei of the preoptic area and in a ventral hypothalamic region corresponding to the nucleus lateralis tuberis. CRF-immunoreactive fibers are observed along the rostral edge of the hypothalamus, in the pituitary stalk, and in the pituitary gland. Within the pituitary, CRF-immunoreactive fibers, with terminal-like boutons, were distinguishable in the neurohypophysis, pars distalis (PD), and pars intermedia (PI). In the PD, the CRF-immunoreactive fibers terminate in regions that contain TSH-positive pituitary cells. From this study, we conclude that CRF-immunoreactive fibers travel through, and terminate in, the neurohypophysis. CRF-immunoreactive fibers were also observed to terminate within the basement membrane and within the PD and PI of the adenohypophysis. Furthermore, the contiguous localization of CRF-immunoreactive fibers and TSH-immunoreactive pituitary cells suggests that CRF may mediate release of TSH.
Matz
S P
SP
Institute of Neuroscience, 1254 University of Oregon, Eugene, Oregon 97403, USA.
Hofeldt
G T
GT
D000818:Animals; D001923:Brain Chemistry; D003346:Corticotropin-Releasing Hormone / Q000032:analysis*; D007150:Immunohistochemistry; D010902:Pituitary Gland / Q000033:anatomy & histology / Q000737:chemistry*; D012474:Salmon / Q000033:anatomy & histology / Q000378:metabolism*; D013972:Thyrotropin / Q000032:analysis*
D013972:Thyrotropin; D003346:Corticotropin-Releasing Hormone