Lakshmana M K, Raju T R
Department of Neurophysiology, National Institute of Mental Health & Neurosciences, Bangalore.
Indian J Med Res. 1996 Sep;104:234-9.
2, 4-Dichloro phenoxy acetic acid (2, 4-D) was given at 100 mg/kg body weight per day by oral intubation from postnatal days 2 to 25 to assess its effect on the levels of norepinephrine (NE), dopamine (DA) and 5-hydroxytryptamine (5-HT) in olfactory bulb (OB), hippocampus (HI), visual cortex (VC), cerebellum (CB) and brainstem (BS). NE levels were increased in OB, HI, VC and BS at 10 days of age. However, by 25 days, NE levels were decreased in OB, HI and VC. DA levels were also increased in OB, HI, VC and CB at 10 days of age and again decreased by 25 days in OB, HI and VC. 5-HT levels were increased in HI, CB and BS at 10 days and in VC and CB at 25 days of age. Reduced acetylcholinesterase (AChE) activity in OB and HI and monoamines in different brain regions at 25 days of age might be responsible for the observed deficits in both acquisition and rate of pedal press response when animals were exposed chronically to 2, 4-D during postnatal brain development.
从出生后第2天至第25天，通过口服插管每天给予2,4-二氯苯氧乙酸（2,4-D）100毫克/千克体重，以评估其对嗅球（OB）、海马体（HI）、视觉皮层（VC）、小脑（CB）和脑干（BS）中去甲肾上腺素（NE）、多巴胺（DA）和5-羟色胺（5-HT）水平的影响。10日龄时，OB、HI、VC和BS中的NE水平升高。然而，到25日龄时，OB、HI和VC中的NE水平下降。10日龄时，OB、HI、VC和CB中的DA水平也升高，到25日龄时，OB、HI和VC中的DA水平再次下降。10日龄时，HI、CB和BS中的5-HT水平升高，25日龄时，VC和CB中的5-HT水平升高。25日龄时，OB和HI中乙酰胆碱酯酶（AChE）活性降低以及不同脑区单胺水平降低，可能是动物在出生后脑发育期间长期接触2,4-D时观察到的踏板按压反应习得和速率缺陷的原因。
