Myenteric neurons of the mouse small intestine. Morphometry and acetylcholinesterase activity.
1. The myenteric plexus of the small intestine of five C57BL/6J male 5-month-old mice was investigated in whole-mount preparations of the muscularis externa by Giemsa staining and by the acetylcholinesterase (AChE) histochemical technique. 2. The neuronal density was 20212 +/- 3038/cm2 (mean +/- SEM) in the duodenum, 21948 +/- 1488/cm2 in the jejunum, and 25048 +/- 2356/cm2 in the ileum. The difference in neuronal density between duodenum and ileum was statistically significant (P < 0.05). The total serosal surface area of the small intestine was about 30.80 +/- 2.90 cm2, and the total number of neurons was estimated at about 690,000. 3. The neuronal cell and nucleus profile areas ranged, respectively, from 23 to 325 microns 2 and from 6 to 95 microns 2 in the small intestine of the mice studied. There were no significant differences in any of the 3 regions in terms of average neuronal cell or nucleus profile areas. 4. For the histochemical demonstration of AChE, the "direct coloring" copper ferrocyanide method was used. AChE-positive nerve fibers were distributed in the myenteric plexus which was formed by a primary meshwork of relatively large nerve bundles and a secondary meshwork of finer nerve bundles. Most of the neurons of the plexus displayed AChE activity in the cytoplasm though the neurons presented different reaction intensities.(ABSTRACT TRUNCATED AT 250 WORDS)
Bor-Seng-Shu
E
E
Departamento de Anatomia, Universidade de São Paulo, Brasil.
Chadi
G
G
Bor-Jiun-Shu
F
F
Ferraz-de-Carvalho
C A
CA
de-Souza
R R
RR
D000110:Acetylcholinesterase / Q000032:analysis*; D000818:Animals; D002452:Cell Count; D004386:Duodenum / Q000294:innervation; D006651:Histocytochemistry; D007082:Ileum / Q000294:innervation; D007421:Intestine, Small / Q000294:innervation*; D007583:Jejunum / Q000294:innervation; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D009197:Myenteric Plexus / Q000033:anatomy & histology* / Q000201:enzymology; D009474:Neurons / Q000737:chemistry
D000110:Acetylcholinesterase