[Circadian rhythm changes of the levels of endogenous insulin in growing rat's blood after functional mandibular protrution].
OBJECTIVE
In order to determine whether the metabolism of the body can be influenced by local functional orthopedic treatments and the relationship between the proliferation and translation of condyle and the metabolism of the body, the author investigates the circadian rhythm of the levels of endogenous insulin (Ins) in growing rats' blood and the changes after functional mandibular protrusion in daytime (8:00-20:00) or nighttime (20:00-8:00).


METHODS
72 4-week-old SD rats were divided equally and randomly into experimental and control groups, and the rats in experimental groups were put on the functional appliances in daytime (8:00-20:00) or nighttime (20:00-8:00). After 7 days, all rats were sacrificed at 0:00, 4:00, 8:00, 12:00, 16:00, 20:00 in a day. Radioimmunoassay methods wore used to detect the levels of endogenous insulin in growing rats' blood in every four hours of a day.


RESULTS
1. The growing rats' blood displayed a significant circadian rhythm in the levels of endogenous insulin, the acrophase was about 13:02. 2. The circadian rhythm still existed after used functional appliance. No significant changes (both mesors and amplitudes) had been observed in the experimental groups comparing with the control groups. 3. The circadian rhythm of insulin in blood concerned with that of endogenous insulin in condyle.


CONCLUSIONS
1. The metabolism of the body can not be influenced by local functional orthopedic treatments. 2. The proliferation and translation of condyle concern with the metabolism of the body.
Xiong
G
G
Department of Stomatology, Shenzhen People's Hospital.
Chen
Y
Y
Ye
L
L
Lou
S
S
D000818:Animals; D002940:Circadian Rhythm; D007328:Insulin / Q000097:blood*; D008297:Male; D008335:Mandibular Condyle / Q000254:growth & development* / Q000378:metabolism; D017289:Orthodontic Appliances, Functional; D051381:Rats; D017207:Rats, Sprague-Dawley
D007328:Insulin