TY - JOUR
T1 - TFMPP, a 5HT(1B) receptor agonist, inhibits light-induced phase shifts of the circadian activity rhythm and c-Fos expression in the mouse suprachiasmatic nucleus
AU - Pickard, Gary E.
AU - Rea, Michael A.
PY - 1997/8/8
Y1 - 1997/8/8
N2 - The hypothalamic suprachiasmatic nucleus (SCN) receives afferents from the retina and the midbrain raphe. The retinal innervation mediates photic entrainment of the SCN circadian oscillator whereas the serotonergic input arising from the midbrain raphe nuclei appears to modulate retinohypothalamic neurotransmission. We hypothesized that serotonergic innervation of the SCN may modulate retinal input by activation of 5HT(1B) presynaptic receptors on retinal axon terminals in the SCN. We tested this hypothesis using the 5HT(1B) receptor agonist, 1-[3- (trifluoromethyl)phenyl]-piperazine (TFMPP). Systemic administration of TFMPP prior to light stimulation significantly attenuated light-induced phase shifts of the circadian activity rhythm and Fos expression in the SCN. These results in the mouse support our earlier findings in the hamster [Pickard, G.E., Weber, E.T., Scott, P.A., Riberdy, A.F. and Pea, M.A., J. Neurosci., 16 (1996) 82088220] and are consistent with the interpretation that 5HT(1B) presynaptic receptors participate in the regulation of photic input to the SCN.
AB - The hypothalamic suprachiasmatic nucleus (SCN) receives afferents from the retina and the midbrain raphe. The retinal innervation mediates photic entrainment of the SCN circadian oscillator whereas the serotonergic input arising from the midbrain raphe nuclei appears to modulate retinohypothalamic neurotransmission. We hypothesized that serotonergic innervation of the SCN may modulate retinal input by activation of 5HT(1B) presynaptic receptors on retinal axon terminals in the SCN. We tested this hypothesis using the 5HT(1B) receptor agonist, 1-[3- (trifluoromethyl)phenyl]-piperazine (TFMPP). Systemic administration of TFMPP prior to light stimulation significantly attenuated light-induced phase shifts of the circadian activity rhythm and Fos expression in the SCN. These results in the mouse support our earlier findings in the hamster [Pickard, G.E., Weber, E.T., Scott, P.A., Riberdy, A.F. and Pea, M.A., J. Neurosci., 16 (1996) 82088220] and are consistent with the interpretation that 5HT(1B) presynaptic receptors participate in the regulation of photic input to the SCN.
KW - 1-[3- (Trifluoromethyl)phenyl]-piperazine
KW - 5HT(1B)
KW - Circadian rhythm
KW - Photic entrainment
KW - Presynaptic
KW - Suprachiasmatic nucleus
KW - c-Fos
UR - http://www.scopus.com/inward/record.url?scp=0030611838&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0030611838&partnerID=8YFLogxK
U2 - 10.1016/S0304-3940(97)00534-X
DO - 10.1016/S0304-3940(97)00534-X
M3 - Article
C2 - 9291149
AN - SCOPUS:0030611838
VL - 231
SP - 95
EP - 98
JO - Neuroscience Letters
JF - Neuroscience Letters
SN - 0304-3940
IS - 2
ER -