Can chronic nasal obstruction cause dysfunction of the paratubal muscles and otitis media? An experimental study in developing Wistar rats.
OBJECTIVE
To quantitatively analyze modifications of the paratubal muscles in developing Wistar rats following nasal obstruction.


METHODS
Twenty-four Wistar rats were used. Twelve were examined at 6, 8 and 12 weeks after birth and were considered normal controls. The nostrils of the remaining 12 rats were bilaterally obstructed by means of a synthetic resin 28 days after birth. The animals were sacrificed at either 2, 4 or 8 weeks after nostril occlusion. Serial sections were made in the dorsoventral plane and stained with hematoxylin-eosin. Four 5 x 5 microm2 areas, selected within the paratubal muscles, were histologically analyzed and the number of muscular fibers was counted manually.


RESULTS
The number of tensor veli palatini muscle fibers progressively decreased in the obstructed rats compared with age-matched normal controls and in those that had been obstructed for 4 and 8 weeks these reductions were statistically significant.


CONCLUSIONS
The correct development of the paratubal muscles seems to be linked to physiological nasal breathing and is negatively affected by oral breathing.
Scarano
E
E
Department of Otolaryngology, Catholic University of Rome, Rome, Italy. iclot@rm.unicatt.it
Fetoni
A R
AR
Picciotti
P
P
Cadoni
G
G
Galli
J
J
Paludetti
G
G
D000818:Animals; D001707:Biopsy, Needle; D002908:Chronic Disease; D004195:Disease Models, Animal; D005064:Eustachian Tube / Q000473:pathology*; D005260:Female; D007150:Immunohistochemistry; D008297:Male; D018485:Muscle Fibers, Skeletal / Q000473:pathology; D015508:Nasal Obstruction / Q000150:complications / Q000473:pathology*; D010034:Otitis Media with Effusion / Q000150:complications* / Q000473:pathology*; D010156:Palatal Muscles / Q000473:pathology* / Q000503:physiopathology; D011336:Probability; D051381:Rats; D017208:Rats, Wistar; D012016:Reference Values; D018570:Risk Assessment