The Expression Of Melatonin Receptor MT₁in Hypothalamus Glial Cell Of Bactrian Camel And Camp Signal Transduction

Melatonin is important for the seasonal adjustment of animal reproductionactivities, but there is no report about whether the melatonin receptor MT₁of bactriancamel is expressed in the hypothalamus glial cells and its signal transduction. Thisexperiment collected the hypothalamus organization of11¹2months bactrian camel,by adopting the method of enzymatic digestion cell culture, molecular biology, Gprotein signal transduction pathway blocking and enzyme-linked immunosorbentassays to study the distribution of MT₁in the hypothalamus glial cells of bactriancamel and the signaling transduction pathways that melatonin involved, and providinga certain amount of basic research to reveal the function of melatonin in mammalianreproductive axis. The research’s results are as follows:（1） Successfully cultivated the hypothalamus glial cells of bactrian camel by themethod of enzyme digestion, through cell subculture,frozen storage and recoveryrepeatedly, to achieve the long-term preservation of cell lines,after manybatches,acquired a lot of hypothalamus glial cells of bactrian camel.（2） Melatonin receptor MT₁（452bp） gene from the hypothalamus glial cells ofbactrian camel was successfully cloned through RT–PCR. Compared with othermammalians, the cloned fragments of MT₁gene is more similar to cow MT₁（87%）than other species. It located in the same evolutionary tree branches of systerm withcattle, sheep, horses and pigs, which explained its homology to these species of MT₁.（3） It is found that melatonin could reduce the cAMP content in thehypothalamus glial cells, as dose increased, the reducing trend decreases gradually.PTX+melatonin and PTX group has the similar effect, has no significant differenceto cAMP production. FSK can cause cAMP significantly increases, cAMPaccumulation in FSK+melatonin group is lower than in PSK group（P<0.05）. Theaccumulated cAMP intracellular of FSK+melatonin group below FSK group,significant difference. These results showed that the different melatonin treatmentscan change the accumulation of cAMP in the hypothalamus glial cells of bactriancamel, and melatonin binding to its receptors can change the accumulation of cAMPin the hypothalamus glial cells of bactrian camel, which played a role in regulatingthe hypothalamus glial cells connection with the inhibitory Gi and stimulating Gspathways sensitivity to the PTX which G protein relying on. Conclusion: Partial MT1gene was cloned from hypothalamus glial cells,explored the cAMP signal transduction pathways that the melatonin of hypothalamusglial cells had involved and provided a new pathway to study melatonin regulating theseasonal reproduction of animal and the mechanism of action of melatonin.