Effects of pineal body and melatonin on lymphocyte proliferation and dinoprostone production in rat spleen.
OBJECTIVE
To determine the effects of pineal body and melatonin (Mel) on lymphocyte proliferation and dinoprostone production in rat spleen.


METHODS
Pinealectomy (PE), lymphocyte proliferation assay and dinoprostone radioimmunoassay were used.


RESULTS
A circadian rhythm of splenic lymphocyte proliferation which peaked at 22:00 was obliterated by PE in rats. PE led to an impairment of lymphocyte proliferation and an increase of dinoprostone production, which were restored by ip Mel 10 micrograms.kg-1.d-1 at 16:00 for 7 d. Mel promoted lymphocyte proliferation and inhibited dinoprostone production in intact rats. A negative correlation between the change in lymphocyte proliferation and dinoprostone production was seen.


CONCLUSIONS
The pineal body and its main hormone Mel play a regulatory role in circadian lymphocyte proliferation which is related to dinoprostone production in rat spleen.
Ding
C H
CH
Institute of Clinical Pharmacology, Anhui Medical University, Hefei, China.
Wei
W
W
Xu
S Y
SY
D000818:Animals; D002455:Cell Division / Q000187:drug effects; D002940:Circadian Rhythm; D015232:Dinoprostone / Q000096:biosynthesis*; D008214:Lymphocytes / Q000166:cytology*; D008297:Male; D008550:Melatonin / Q000494:pharmacology / Q000502:physiology*; D010870:Pineal Gland / Q000502:physiology* / Q000601:surgery; D051381:Rats; D017207:Rats, Sprague-Dawley; D013154:Spleen / Q000166:cytology / Q000378:metabolism*
D008550:Melatonin; D015232:Dinoprostone