ABSTRACT
Calcitonin gene-related peptide (CGRP) is a neuropeptide coded by the calcitonin gene and divided into α and β subtypes. CGRP is widely distributed throughout the human body and highly expressed in the peripheral and central nervous system. Studies have shown that CGRP plays a role in a variety of physiological and pathophysiological activities, such as the formation and transmission of nociceptive signal, as well as the regulation of cardiovascular function. Recently, more and more researches have shown that CGRP is involved in the regulation of synaptic plasticity, cognitive function and learning memory in the central nervous system. This paper reviews the role of CGRP in regulation of synaptic plasticity and process of emotional memory, hoping to provide a new molecular target and theoretical basis for clinical treatment of neurological diseases.
Subject(s)
Humans , Calcitonin , Calcitonin Gene-Related Peptide , Central Nervous System , Memory , Neuronal PlasticityABSTRACT
Objective: To observe the effect of extracts from Ginseng Radix et Rhizoma,Anemarrhenae Rhizoma and Paeoniae Radix Rubra on N-methyl-D-aspartate receptors(NMDAR1) in hippocampal neurons in rats with vascular dementia and investigate its possible mechanism. Method: The 60 SPF male rats were randomly divided into normal group, sham-operated group,model group, traditional Chinese medicine group(0.20 g·kg-1)and memantine group(2.1 mg·kg-1),with 12 rats in each group. The model was established by repeated ischemia-reperfusion combined with intraperitoneal injection of sodium nitroprusside. After modelling, normal group, sham-operated group and model group were dosed the similar volume of normal saline once a day for 14 days. The learning and memory capacity was assessed by Morris water maze; pathologic change in the CA1 district of hippocampus was assessed by hematoxylin-eosin (HE) staining, and the expression level of NMDAR1 in hippocampal neuron membrane protein was detected by Western blot and immunohistochemistry(IHC),the NMDAR1 mRNA in hippocampal tissue was detected by Real-time PCR. Result:Compared with normal and sham-operated group, the latency period was prolonged in model group(PPPPPPPPConclusion:The extracts from Ginseng Radix et Rhizoma,Anemarrhenae Rhizoma and Paeoniae Radix Rubra can improve the learning and memory capacity of rats with vascular dementia, and alleviate the injury in CA1 district of hippocampus. The mechanism may be related to the down-regulation of NMDAR1 expression in hippocampal neurons.
ABSTRACT
The purpose of this study was to explore the effects of calcitonin gene-related peptide (CGRP) on the long-term depression (LTD) of hippocampus in mice. Sixty C57BL/6J mice (30 days old) were randomly divided into control group, three CGRP (50, 100, and 200 nmol/L) groups, CGRP + CGRP group and CGRP + APV group (10 mice for each group). The effects of exogenous application of different concentrations of CGRP on synaptic plasticity and LTD in hippocampus of mice were detected by in vitro recording of local field potential. The results showed that higher doses (100 and 200 nmol/L) of CGRP significantly enhanced the induction of LTD in the hippocampus. Moreover, CGRP increased the magnitude of N-methyl-D-aspartate (NMDA) receptor-mediated excitatory postsynaptic currents. The above-mentioned effects of CGRP were blocked by either CGRP selective antagonist CGRP or NMDA receptor antagonist APV. These results suggest that CGRP can dose-dependently enhance the induction of LTD in hippocampus of mice, and the underlying mechanism involves the mediation of NMDA receptor function.
Subject(s)
Animals , Mice , Calcitonin Gene-Related Peptide , Pharmacology , Hippocampus , Long-Term Synaptic Depression , Mice, Inbred C57BL , Random AllocationABSTRACT
Raffinose series oligosaccharides are the transport and storage sugars of many plants, Rehmannia glutinosa is one of the commonly used Chinese herbal medicines, medicinal parts ist he roots. Root and tuber of R. glutinosa contains stachyose, raffinose and other oligosaccharides, but the study about the process of growth and development of other organs in the non-structural changes in sugar content is rare.In this study, leaves, stems and roots of R. glutinosa were used as materials to analyze the diurnal variation and the changes of sugar content of sucrose, raffinose and stachyose in different organs of R. glutinosa. The results showed that the content of sucrose in R. glutinosa leaves gradually increased from seedling stage.However, the content of stachyose did not change much at the early stage of growth, and the stachyose rapidly increased at the later stage of growth. The raffinose content gradually decreased throughout the growing season, young leaves of R. glutinosa have higher ability to sucrose synthesis than mature leaves, while mature leaf has higher raffinose and stachyose synthesis ability than young leaves. Sucrose and stachyose content in stem gradually increased, while there was little change in raffinose content. The content of raffinose and stachyose in root increased rapidly from the beginning of fast growing period, while the content of sucrose did not change much. The content of sucrose in leaves of R. glutinosa did not change much at day and night, while the daily changes of raffinose and stachyose contents were very obvious. The contents of raffinose and stachyose in daytime were higher than those at night. The content of raffinose in root and stem was not changed much, but the change of stachyose in root, stem and leaf was very obvious, especially in stem and leaf. In summary, the leaf is the main synthetic organ of raffinose, leaves, stems and roots are stachyose synthesis organ. Sucrose, raffinose and stachyose are the major transport forms of carbohydrates in R. glutinosa.