TY - JOUR
T1 - Palisade Endings Are a Constant Feature in the Extraocular Muscles of Frontal-Eyed, But Not Lateral-Eyed, Animals
AU - Blumer, Roland
AU - Maurer-Gesek, Barbara
AU - Gesslbauer, Bernhard
AU - Blumer, Michael
AU - Pechriggl, Elisabeth
AU - Davis-López de Carrizosa, María A
AU - Horn, Anja K
AU - May, Paul J
AU - Streicher, Johannes
AU - de la Cruz, Rosa R
AU - Pastor, Ángel M
N1 - Publisher Copyright:
© 2016. Sci all right reserved.
PY - 2016/2
Y1 - 2016/2
N2 - PURPOSE: To test whether palisade endings are a general feature of mammalian extraocular muscles (EOMs).METHODS: Thirteen species, some frontal-eyed (human, monkey, cat, and ferret), and others lateral-eyed (pig, sheep, calf, horse, rabbit, rat, mouse, gerbil, and guinea pig) were analyzed. Palisade endings were labeled by using different combinations of immunofluorescence techniques. Three-dimensional reconstructions of immunolabeled palisade endings were done.RESULTS: In all frontal-eyed species, palisade endings were a consistent feature in the rectus EOMs. Their total number was high and they exhibited an EOM-specific distribution. In particular, the number of palisade endings in the medial recti was significantly higher than in the other rectus muscles. In the lateral-eyed animals, palisade endings were infrequent and, when present, their total number was rather low. They were only found in ungulates (sheep, calf, pig, and horse) and in rabbit. In rodents (rat, guinea pig, mouse, and gerbil) palisade endings were found infrequently (e.g., rat) or were completely absent. Palisade endings in frontal-eyed species and in some lateral-eyed species (pig, sheep, calf, and horse) had a uniform morphology. They generally lacked α-bungarotoxin staining, with a few exceptions in primates. Palisade endings in other lateral-eyed species (rabbit and rat) exhibited a simplified morphology and bound α-bungarotoxin.CONCLUSIONS: Palisade endings are not a universal feature of mammalian EOMs. So, if they are proprioceptors, not all species require them. Because in frontal-eyed species, the medial rectus muscle has the highest number of palisade endings, they likely play a special role in convergence.
AB - PURPOSE: To test whether palisade endings are a general feature of mammalian extraocular muscles (EOMs).METHODS: Thirteen species, some frontal-eyed (human, monkey, cat, and ferret), and others lateral-eyed (pig, sheep, calf, horse, rabbit, rat, mouse, gerbil, and guinea pig) were analyzed. Palisade endings were labeled by using different combinations of immunofluorescence techniques. Three-dimensional reconstructions of immunolabeled palisade endings were done.RESULTS: In all frontal-eyed species, palisade endings were a consistent feature in the rectus EOMs. Their total number was high and they exhibited an EOM-specific distribution. In particular, the number of palisade endings in the medial recti was significantly higher than in the other rectus muscles. In the lateral-eyed animals, palisade endings were infrequent and, when present, their total number was rather low. They were only found in ungulates (sheep, calf, pig, and horse) and in rabbit. In rodents (rat, guinea pig, mouse, and gerbil) palisade endings were found infrequently (e.g., rat) or were completely absent. Palisade endings in frontal-eyed species and in some lateral-eyed species (pig, sheep, calf, and horse) had a uniform morphology. They generally lacked α-bungarotoxin staining, with a few exceptions in primates. Palisade endings in other lateral-eyed species (rabbit and rat) exhibited a simplified morphology and bound α-bungarotoxin.CONCLUSIONS: Palisade endings are not a universal feature of mammalian EOMs. So, if they are proprioceptors, not all species require them. Because in frontal-eyed species, the medial rectus muscle has the highest number of palisade endings, they likely play a special role in convergence.
KW - Animals
KW - Bungarotoxins/metabolism
KW - Cats
KW - Cattle
KW - Choline O-Acetyltransferase/metabolism
KW - Ferrets
KW - Fluorescent Antibody Technique, Indirect
KW - Functional Laterality/physiology
KW - Gerbillinae
KW - Guinea Pigs
KW - Horses
KW - Humans
KW - Macaca
KW - Mice
KW - Microscopy, Confocal
KW - Motor Neurons/physiology
KW - Nerve Endings/physiology
KW - Neurofilament Proteins/metabolism
KW - Ocular Physiological Phenomena
KW - Oculomotor Muscles/innervation
KW - Proprioception/physiology
KW - Rabbits
KW - Rats
KW - Sensory Receptor Cells/metabolism
KW - Sheep
KW - Swine
UR - http://www.scopus.com/inward/record.url?scp=84957061981&partnerID=8YFLogxK
U2 - 10.1167/iovs.15-18716
DO - 10.1167/iovs.15-18716
M3 - Journal article
C2 - 26830369
SN - 0146-0404
VL - 57
SP - 320
EP - 331
JO - Investigative Ophthalmology and Visual Science
JF - Investigative Ophthalmology and Visual Science
IS - 2
ER -