Comparative study of sensitive and vegetative innervation of external and internal anal sphincter muscles in different mammals.
Proprioceptive innervation of the external anal sphincter muscle and the organization of the vegetative and sensitive nerve components of the internal and sphincter muscle have been studied in different mammals. The findings of typical muscle spindles in the external anal sphincter muscle were constant in the pig, frequent in the goat and cow, rare in the sheep and horse and absent in the roe and rabbit. In the pig, muscle spindles were observed in the entire extension of the muscle, while in the sheep, goat, cow and horse, the receptors were found only in the cranial portion of the muscle. In all the species studied, the internal anal sphincter muscle had numerous ganglion cells, isolated or grouped, and rare Pacinian, Pacinian-like, and Golgi-Mazzoni corpuscles. Their functional role has been hypothesized.
Panu
R
R
Institute of Normal Anatomy of Domestic Animals, Faculty of Veterinary Medicine, University of Parma.
Bo Minelli
L
L
Sanna
L
L
Acone
F
F
Zedda
M
M
Gazza
F
F
Palmieri
G
G
D001003:Anal Canal / Q000033:anatomy & histology / Q000294:innervation*; D000818:Animals; D002417:Cattle; D003670:Deer; D005260:Female; D006041:Goats; D006736:Horses; D008297:Male; D008322:Mammals / Q000033:anatomy & histology*; D008465:Mechanoreceptors / Q000166:cytology; D018482:Muscle, Skeletal / Q000033:anatomy & histology / Q000294:innervation*; D009130:Muscle, Smooth / Q000033:anatomy & histology / Q000294:innervation*; D011817:Rabbits; D012756:Sheep; D013045:Species Specificity; D013552:Swine