Study On The Seasonal Rhythm Of Differential Expression Of Melatonin Receptor (MTNR1a) MRNA In Mongolia Sheep

Eight Mongolia Sheep were selected respectively at vernal equinox, summer solstice, autumnal equinox, winter solstice, which had good physical condition and similar body weights, then total RNA was extracted from hypothalamus and pituitary obtained from the sheep with the method of surgery, after optimization of reaction conditions and system, though RT-PCR(semi-quantitative reverse transcription and polymerase Chain reaction , SqRT-PCR)with the separated tube , the expression of melatonin receptor Gene (MTNR1a) in hypothalamus and pituitary were studied and expression of melatonin receptor mRNA was also detected in four seasons. This study in order to declare that whether the expression of melatonin receptor 1a gene mRNA had the rhythm and the effect of rhythm on the sheep seasonal reproduction. The results were showed as follows:1. The content of melatonin receptor had seasonal rhythm changes in hypothalamus for Mongolia sheep, the content of melatonin receptor was the minimum at summer solstice and maximum at autumnal equinox and the latter was significantly more than former; there was no significant difference between the content of melatonin receptor at spring and winter but latter was more than former slightly.2. The content of melatonin receptor also had seasonal rhythm changes in pituitary for Mongolia sheep, the content of melatonin receptor was the minimum at autumnal equinox and maximum at summer solstice and the latter was significantly more than former; there was no significant difference between the content of melatonin receptor at spring and winter but latter was more than former slightly.3. Expression of melatonin receptor gene was the maximum in hypothalamus and minimum in pituitary in autumn but other three seasons.