Yizhen  Wang, E.  Xu, Linna  Zhu, Ren  Lai, Jia  Guo, Yanna  Huang, Ting  Wu, 
    Expression Patterns of the <i>Cannabinoid Receptor 1</i> Gene in Pig Skeletal Muscle and Skeletal Satellite Muscle Cells,
    Journal of Animal and Veterinary Advances,
    Volume 11,Issue 23,
    2012,
    Pages 4297-4303,
    ISSN 1680-5593,
    javaa.2012.4297.4303,
    (https://makhillpublications.co/view-article.php?doi=javaa.2012.4297.4303)
    Abstract: The Cannabinoid Receptor type 1 (CNR1) is a key component 
  of the endocannabinoid system which has been reported to play a pivotal role 
  in modulating feeding behavior and energy balance. While a large number of researches 
  have showed clearly that CNR1 is expressed in skeletal muscle of mice and human 
  beings, detailed analysis of <I>CNR1</I> gene expression in pig muscles and 
  muscle cells has not been reported. Here, quantitative PCR were used to characterize 
  the CNR1 in different muscles of pig and isolation of porcine myogenic satellite 
  cells. Results showed that the expression of CNR1 mRNA was greatest in longissimus 
  dorsi muscle (p&lt;0.01) among that in the gastrocnemius (mix), soleus muscle 
  (slow-type) and longissimus doris muscle (fast-type). As to age-related changes 
  of <I>CNR1</I> gene in different pig muscles, the higher expression was found 
  at the 30th day, then declined (p&lt;0.05) in all three kinds of muscles to 
  the 90th day. At the 150th day, the expression of CNR1 steadily decreased (p&lt;0.05) 
  in the gastrocnemius compared to the 90th day but not in longissimus doris muscle 
  and soleus. Meanwhile the breed differences in the expression of CNR1 mRNA between 
  Jinhua pig and Landrace were also identified. The mRNA abundance of CNR1 in 
  Landrace was higher compared with that of Jinhua pigs and strong differences 
  were observed in longissimus doris muscle (p&lt;0.05) and soleus (p&lt;0.01). 
  <I>In vitro</I> with the differentiation of the satellite cells, the mRNA expression 
  of the CNR1 was significantly down-regulated (p&lt;0.05). The lowest mRNA expression 
  was observed at the 9th day. These data provide a framework of <I>CNR1</I> gene 
  expression patterns and implicate a novel gene for regulating muscle fiber types.
    Keywords: Cannabinoid Receptor 1 (CNR1);skeletal muscle;skeletal satellite muscle cells;pig;isolation;gastrocnemius;China