F. Gauer et al., EFFECT OF A LIGHT-PULSE ON MELATONIN RECEPTOR DENSITY AND MESSENGER-RNA EXPRESSION IN SIBERIAN HAMSTER SUPRACHIASMATIC NUCLEI, Neuroscience letters, 233(1), 1997, pp. 49-52
Melatonin receptors located in the suprachiasmatic nuclei (SCN) have b
een cloned in mammals hypothalamus. We previously reported a SCN melat
onin receptor photic regulation in the rat. The present study's aim wa
s to investigate whether a photic regulation of both melatonin recepto
r density and mRNA expression takes place in the SCN of a highly photo
periodic species, the Siberian hamster. To achieve this goal, we first
set up an in situ hybridization protocol without RNase treatment to a
llow a highly sensitive and reproducible quantitative analysis of mela
tonin receptor mRNA expression. Results showed that a 1 h light pulse
delivered during night-time did not affect SCN melatonin binding capac
ities while it induced a strong increase of the melatonin receptor mRN
A expression in the SCN of pinealectomized animals. (C) 1997 Elsevier
Science Ireland Ltd.