ABSTRACT
AIM:To explore the expression and possible function of histamine H3 receptor (H3R) in striated myogenesis and the differentiated C2C12 cells.METHODS: H3R and myogenesis late marker myosin heavy chain (MHC) were detected at mRNA and protein levels during C2C12 myogenesis.H3R antagonist ciproxifan was added and the expression of the myogenesis early marker desmin, intermediate markers myogenin and MHC was detected.Differentia-ted myoblasts were loaded with Fluo-4 calcium indicator dye and the effect of R-( a)-methylhistamine ( RMeHA) on the cy-toplasmic calcium concentration was determined under the 200 mA electrical stimulation.RESULTS: The expression of H3R and MHC was increased during myogenesis.Ciproxifan incubation had no influence on the 3 striated myogenesis mar-kers (P>0.05).In C2C12 myoblasts, RMeHA (10 nmol/L~100 μmol/L) effectively diminished cytoplasmic calcium peak when the cells were electrically paced (P<0.05).The best inhibitory effect of RMeHA was observed at dose of 100 nM for 10 min and 20 min, which was higher than that for 5 min (P<0.05).CONCLUSION: H3R might have little effect on the myogenic differentiation, but diminishes cytoplasmic calcium peak of the differentiated myoblasts under electri-cal stimulation.
ABSTRACT
Objective To explore the anti-convulsion action of histamine(HA) in the central system and treatment of histamine H3 receptor(H3R) antagonists to rat model with intractable epilepsy.Methods 88 Wistar rats(12-day-old) were randomly divided into three groups:normal control group,N-methyl-D-aspartate(NMDA) group and betahistine(BH) groups(including high and low dose BH groups).Wistar rats received an intraperitoneal NMDA administration to make animal model of intractable epilepsy at infant period and toddler age.After that,the rats were observed daily for latencies and incidences to two NMDA-dependent stereotypical behaviors.The HA content of each brain region was determined with fluorimetry,and H3R were evaluated with immunohistochemical method.Results The automatisms including tail twisting and emprosthotonus seizures of(12-17)-day-old rats were observed in NMDA and BH groups.The rats,aged 18-25 d,became quiet following automatisms rather than emprothotonic.Compared with NMDA group,BH groups had longer latencies and lower incidences of tail twisting and emprosthotonus(P0.05).Conclusion The NMDA-induced model is similar to the clinical manifest of human West syndrome.It is up to animal model of intractable epilepsy at infant period and toddler age.The HA content of brain region is negatively related with seizure incidence.H3R antagonists have certain therapeutic function to intractable epilepsy in rats at infant period and toddler age.
ABSTRACT
The intracellular signal transduction pathway of histamine H 3 receptor was reviewed. The modulatory effect to some neurotransmitters on cardiovascular system and the therapeutic potential of histamine H 3 receptor agonist was summarized.