[Protection of lithium on hippocampal cholecystokinin and nitric oxide synthase neuron in lead exposed rats].
OBJECTIVE
To investigate the effect of lithium on hippocampal cholecystokinin (CCK) and neuronal nitric oxide synthase (nNOS) positive neurons and its relationship to the learning and memory ability of lead exposed rats.


METHODS
Wistar rats were randomly divided into the control group, the lead group, four lead + LiCl (3, 30, 300, 3,000 mg/kg) groups. Four lead + LiCl groups were fed with food containing 3, 30, 300, 3,000 mg/kg LiCl respectively. The lead + LiCl groups and the lead group were administered with distilled water containing 0.2% PbAc. The body weight was measured and the difference of body development was observed. Y-maze test was used for studying the effects of lead on the learning and the memory ability in rats. ABC immunohistochemistry was used for investigating the changes of CCK positive neurons in hippocampus of lead-exposed rats.


RESULTS
Compared with the control group and the lead + LiCl groups, the learning and memory ability of lead exposed rats was significantly higher (P < 0.05). The number of CCK positive neurons in hippocampus lead exposed rats fed with lithium (3, 30, 300 mg/kg) was significantly higher than that in the lead exposed rats (P < 0.05).


CONCLUSIONS
The lead may damage the learning-memory ability of the rats. It might be related to the changes of CCK positive neurons in hippocampus in lead exposed rats. The lithium of the low dose might play an important role in preventing lead-induced damages.
Li
Ji-sheng
JS
Military Preventive Medical Institute, Medical College of Chinese People's Armed Police Forces, Tianjin 300162, China.
Yang
Fang
F
Zhao
Xin
X
D000818:Animals; D002766:Cholecystokinin / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D006624:Hippocampus / Q000187:drug effects* / Q000378:metabolism; D007150:Immunohistochemistry; D007854:Lead / Q000633:toxicity*; D008094:Lithium / Q000494:pharmacology*; D008297:Male; D018782:Maze Learning / Q000187:drug effects; D008568:Memory / Q000187:drug effects; D009474:Neurons / Q000201:enzymology; D019001:Nitric Oxide Synthase / Q000378:metabolism*; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar
D007854:Lead; D002766:Cholecystokinin; D008094:Lithium; D019001:Nitric Oxide Synthase