http://hdl.handle.net/2027.42/78407 Fri, 24 May 2013 13:22:07 GMT 2013-05-24T13:22:07Z http://deepblue.lib.umich.edu:80/bitstream/id/280015/216680.gif http://hdl.handle.net/2027.42/78407 http://hdl.handle.net/2027.42/75751 Hypocretin-1 causes G protein activation and increases ACh release in rat pons Bernard, René; Lydic, Ralph; Baghdoyan, Helen A. The effects of the arousal-promoting peptide hypocretin on brain stem G protein activation and ACh release were examined using 16 adult Sprague-Dawley rats. In vitro [ 35 S]GTPγS autoradiography was used to test the hypothesis that hypocretin-1-stimulated G protein activation is concentration-dependent and blocked by the hypocretin receptor antagonist SB-334867. Activated G proteins were quantified in dorsal raphe nucleus (DR), locus coeruleus (LC) and pontine reticular nucleus oral part (PnO) and caudal part (PnC). Concentration–response data revealed a significant ( P  < 0.001) effect of hypocretin-1 (2–2000 nm) in all brain regions examined. Maximal increases over control levels of [ 35 S]GTPγS binding were 37% (DR), 58% (LC), 52% (PnO) and 44% (PnC). SB-334867 (2 µm) significantly ( P  < 0.002) blocked hypocretin-1 (200 nm)-stimulated [ 35 S]GTPγS binding in all four nuclei. This is the first autoradiographic demonstration that hypocretin-1 activates G proteins in arousal-related brain stem nuclei as a result of specific receptor interactions. This finding suggests that some hypocretin receptors in brain stem couple to inhibitory G proteins. In vivo microdialysis was used to test the hypothesis that PnO administration of hypocretin-1 increases ACh release in PnO. Dialysis delivery of hypocretin-1 (100 µm) significantly ( P  < 0.002) increased (87%) ACh release. This finding is consistent with the interpretation that one mechanism by which hypocretin promotes arousal is by enhancing cholinergic neurotransmission in the pontine reticular formation. Wed, 01 Oct 2003 00:00:00 GMT http://hdl.handle.net/2027.42/75751 2003-10-01T00:00:00Z http://hdl.handle.net/2027.42/75723 Roles of residues 3 and 4 in cyclic tetrapeptide ligand recognition by the Κ -opioid receptor Przydzial, M. J.; Pogozheva, I. D.; Bosse, K. E.; Andrews, S. M.; Tharp, T. A.; Traynor, John R.; Mosberg, Henry I. Tue, 01 Mar 2005 00:00:00 GMT http://hdl.handle.net/2027.42/75723 2005-03-01T00:00:00Z http://hdl.handle.net/2027.42/75634 VISUALLY EVOKED RESPONSE IN ANESTHETIZED MAN WITH AND WITHOUT INDUCED MUSCLE PARALYSIS * Domino, Edward F.; Corssen, Guenter Fri, 01 May 1964 00:00:00 GMT http://hdl.handle.net/2027.42/75634 1964-05-01T00:00:00Z http://hdl.handle.net/2027.42/75625 EFFECT OF INFARCT SIZE LIMITATION BY PROPRANOLOL ON VENTRICULAR ARRHYTHMIAS AFTER MYOCARDIAL INFARCTION Stewart, James R.; Gibson, John K.; Lucchesi, Benedict R. Mon, 01 Mar 1982 00:00:00 GMT http://hdl.handle.net/2027.42/75625 1982-03-01T00:00:00Z