[The effect of prenatal exposure to cadmium on flash visual evoked potentials in rat offspring before and after injection of norepinephrine into the lateral brain ventricle].
OBJECTIVE
It is known that norepinephrine (NE) in low doses increases the amplitude of flash visual evoked potential (FVEP). The purpose of this paper was to find out if cadmium (Cd) intoxication changes the NE effect on FVEP.


METHODS
18 Wistar albino rats were divided into 3 groups: 6 received 5 ppm, next 6 received 50 ppm cadmium in drinking water since time of conception and during 21 days after delivery and 6 as a control group received tap water only. Newborns were examined when they were 3 to 6 months old. FVEP were recorded before and after injection of 10 microliters saline and then NE into the right lateral brain ventricle. Two doses of NE 25 and 50 nmols were used. Amplitudes of the first deep negative wave (N1) and the next positive one (P2) were measured from isoelectric line to peaks. For statistic analysis the Student t-test was performed with statistical significance by p < 0.05.


RESULTS
The prolongation of N1 and P2 latencies of FVEP was observed in all groups after both doses of NE, the differences were statistically significant after doses of 25 nmols NE. The amplitude of N1 increased after NE in all groups, in the control one till 205-225% and 143-151% in Cd groups. The amplitude of P2 in control group was higher (109-113%) after NE compared to initial value (100%). Cadmium caused the decrease (of 56-90%) after both doses of NE. The differences of amplitudes were statistically significant. The prenatal treatment by cadmium caused the lower sensitivity of FVEP to NE.
Herba
E
E
Katedry i Oddziału Klinicznego Okulistyki Slaskiej AM w Katowicach, Szpital Specjalistyczny Nr 1 w Bytomiu.
Pojda-Wilczek
D
D
Pojda
S M
SM
Brus
R
R
Plech
A
A
D000284:Administration, Oral; D000818:Animals; D002104:Cadmium / Q000633:toxicity*; D005074:Evoked Potentials, Visual / Q000187:drug effects*; D005260:Female; D007276:Injections, Intraventricular; D008297:Male; D009638:Norepinephrine / Q000008:administration & dosage; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects; D051381:Rats; D017208:Rats, Wistar; D011930:Reaction Time / Q000187:drug effects
D002104:Cadmium; D009638:Norepinephrine