AIM: To investigate the effects of green flickering light on refractive development and expression of muscarinic acetylcholine receptor(mAChR) M1 in the eyes of guinea pigs.METHODS: Thirty guinea pigs(15-20 days old) ...AIM: To investigate the effects of green flickering light on refractive development and expression of muscarinic acetylcholine receptor(mAChR) M1 in the eyes of guinea pigs.METHODS: Thirty guinea pigs(15-20 days old) were randomly divided into three groups(n=10/group). Animals in group I were raised in a completely closed carton with green flickering light illumination. Those in group II were kept in the open top closed carton under normal natural light. Guinea pigs were raised in a sight-widen cage under normal natural light in group III. The refractive status and axial length were measured before and after 8 weeks' illumination. Moreover, total RNA extracted from retinal, choroidal, and scleral tissues were determined by real-time reverse transcription polymerase chain reaction(RT-PCR). The expressions of the receptor M1 were also explored in the retina, choroid, and sclera using immunohistochemistry.RESULTS: There was a remarkable reduction in refractive error and increase in axial length after 8-weeks' green flickering light stimulation(P<0.001). The expression of M1 receptor mRNA in sclera and retina in myopia group were remarkably lower than that in group II and III(P<0.01). Significant reduced expression of M1 receptor stimulated by green flickering light in retina and sclera tissues were also observed(P<0.05). However, there was no M1 receptor expression in choroid in 3 groups.CONCLUSION: Myopia can be induced by 8 weeks' green flickering light exposure in the animal model. M1 receptor may be involved causally or protectively in myopia development.展开更多
We collected centric diatom Stephanopyxis palmeriana samples in coastal waters of Xiamen for charac- teristic red light/far red light (R/FR) phytochrome reactions to identify its photoreceptor in the course of sexual ...We collected centric diatom Stephanopyxis palmeriana samples in coastal waters of Xiamen for charac- teristic red light/far red light (R/FR) phytochrome reactions to identify its photoreceptor in the course of sexual repro- duction. The result showed that pre-illumination of 2-3h red light before darkness could induce sexualization of S. palmeriana, while the follow-up illumination of far red light could reverse the effect of red light, which is a featured reaction of phytochrome. The Southern Dot Blot was carried out to identify the type of phytochrome that induces the sexualization. The result also showed high homogeneity of DNA fragment of S. palmeriana with phyB, but phyA. This means the photoreceptor in the process of sexual reproduction of S. palmeriana is phytochrome B (phyB).展开更多
Based on previous work, it has been hypothesized that the energetics of ultraviolet (UV) light disrupts effects induced by receptor-binding ligands. If this hypothesis is true, then UV light should (i) disrupt a broad...Based on previous work, it has been hypothesized that the energetics of ultraviolet (UV) light disrupts effects induced by receptor-binding ligands. If this hypothesis is true, then UV light should (i) disrupt a broad variety of endpoints and (ii) disrupt effects produced by ligands that bind to diverse receptor types. This was tested directly in the present study by using ligands selective for four different receptors (one ionotropic, three metabotropic) and three different behavioral endpoints. The selective dopamine D2 receptor antagonist (–)sulpiride (0.1 uM) dose-relatedly decreased spontaneous locomotor velocity, the selective nicotinic acetylcholine receptor agonist nicotine (1, 3, 5 mM) and the selective muscarinic acetylcholine receptor agonist pilocarpine (20, 30, 50 mM) induced seizure-like activity, and the selective-opioid receptor agonist U-50,488H (10 uM) produced physical dependence (manifested as abstinence-induced withdrawal) in planarian models. Each of these diverse ligand and receptor-mediated effects were attenuated by UV light (254 nm = 7.83 × 10–19 J = 4.89 eV). These findings provide further evidence that UV light disrupts ligand-receptor mediated interactions and that UV light might provide a useful tool for examining drug-receptor interactions.展开更多
A number of studies have shown that oxidative stress can be harmful for the retina. The real causal circumstances that lead to degenerative diseases like age related macular degeneration remain obscure. Whether light ...A number of studies have shown that oxidative stress can be harmful for the retina. The real causal circumstances that lead to degenerative diseases like age related macular degeneration remain obscure. Whether light induced radical stress is a direct interaction of light with photoreceptors or a secondary mechanism within the pigment epithelium or choroid is in discussion. Among the molecular mechanisms involved are production of reactive oxygen species(ROS), secondary lipid peroxidation, protein oxidation and DNA-damage. The initial trigger to write this review was first a recent finding of our group that the photoreceptor outer segments produce great amounts of ROS and second the detection of ectopic enzymes of the respiratory chainlocalized there- in addition to the hitherto known ROS sources like the visual pigments with their intermediates and the photoreceptor mitochondria harbouring the respiratory chain.展开更多
基金Supported by the National Science Foundation, USA, grants MCB 0091384 and 0444504 to WRB, MCB0444390 to RAB, and by the UK Biotechnology and Biological Sciences Research Council, grant BB/C000366/1 to JMC. Publication of this paper is supported by the National Natural Science Foundation of China （30624808） and Science Publication Foundation of the Chinese Academy of Sciences.
基金Supported by Qilu Hospital of Shandong University (No.201805049)
文摘AIM: To investigate the effects of green flickering light on refractive development and expression of muscarinic acetylcholine receptor(mAChR) M1 in the eyes of guinea pigs.METHODS: Thirty guinea pigs(15-20 days old) were randomly divided into three groups(n=10/group). Animals in group I were raised in a completely closed carton with green flickering light illumination. Those in group II were kept in the open top closed carton under normal natural light. Guinea pigs were raised in a sight-widen cage under normal natural light in group III. The refractive status and axial length were measured before and after 8 weeks' illumination. Moreover, total RNA extracted from retinal, choroidal, and scleral tissues were determined by real-time reverse transcription polymerase chain reaction(RT-PCR). The expressions of the receptor M1 were also explored in the retina, choroid, and sclera using immunohistochemistry.RESULTS: There was a remarkable reduction in refractive error and increase in axial length after 8-weeks' green flickering light stimulation(P<0.001). The expression of M1 receptor mRNA in sclera and retina in myopia group were remarkably lower than that in group II and III(P<0.01). Significant reduced expression of M1 receptor stimulated by green flickering light in retina and sclera tissues were also observed(P<0.05). However, there was no M1 receptor expression in choroid in 3 groups.CONCLUSION: Myopia can be induced by 8 weeks' green flickering light exposure in the animal model. M1 receptor may be involved causally or protectively in myopia development.
基金Supported by National Natural Science Foundation of China (No. 39670076)
文摘We collected centric diatom Stephanopyxis palmeriana samples in coastal waters of Xiamen for charac- teristic red light/far red light (R/FR) phytochrome reactions to identify its photoreceptor in the course of sexual repro- duction. The result showed that pre-illumination of 2-3h red light before darkness could induce sexualization of S. palmeriana, while the follow-up illumination of far red light could reverse the effect of red light, which is a featured reaction of phytochrome. The Southern Dot Blot was carried out to identify the type of phytochrome that induces the sexualization. The result also showed high homogeneity of DNA fragment of S. palmeriana with phyB, but phyA. This means the photoreceptor in the process of sexual reproduction of S. palmeriana is phytochrome B (phyB).
文摘Based on previous work, it has been hypothesized that the energetics of ultraviolet (UV) light disrupts effects induced by receptor-binding ligands. If this hypothesis is true, then UV light should (i) disrupt a broad variety of endpoints and (ii) disrupt effects produced by ligands that bind to diverse receptor types. This was tested directly in the present study by using ligands selective for four different receptors (one ionotropic, three metabotropic) and three different behavioral endpoints. The selective dopamine D2 receptor antagonist (–)sulpiride (0.1 uM) dose-relatedly decreased spontaneous locomotor velocity, the selective nicotinic acetylcholine receptor agonist nicotine (1, 3, 5 mM) and the selective muscarinic acetylcholine receptor agonist pilocarpine (20, 30, 50 mM) induced seizure-like activity, and the selective-opioid receptor agonist U-50,488H (10 uM) produced physical dependence (manifested as abstinence-induced withdrawal) in planarian models. Each of these diverse ligand and receptor-mediated effects were attenuated by UV light (254 nm = 7.83 × 10–19 J = 4.89 eV). These findings provide further evidence that UV light disrupts ligand-receptor mediated interactions and that UV light might provide a useful tool for examining drug-receptor interactions.
文摘A number of studies have shown that oxidative stress can be harmful for the retina. The real causal circumstances that lead to degenerative diseases like age related macular degeneration remain obscure. Whether light induced radical stress is a direct interaction of light with photoreceptors or a secondary mechanism within the pigment epithelium or choroid is in discussion. Among the molecular mechanisms involved are production of reactive oxygen species(ROS), secondary lipid peroxidation, protein oxidation and DNA-damage. The initial trigger to write this review was first a recent finding of our group that the photoreceptor outer segments produce great amounts of ROS and second the detection of ectopic enzymes of the respiratory chainlocalized there- in addition to the hitherto known ROS sources like the visual pigments with their intermediates and the photoreceptor mitochondria harbouring the respiratory chain.
