Low-level cadmium exposure increases one-way avoidance in juvenile rats.
Twenty-seven pregnant rats from three genetic lines, Roman High Avoidance (RHA), Roman Low Avoidance (RLA), and Satinder's Heterogeneous Stock (SHS), received daily SC injections of either 0.075 mg/kg CdCl2 (low dose), 0.225 mg/kg CdCl2 (high dose), or an equivalent volume of saline vehicle (control) throughout gestation. Cd-exposed progeny from the RHA genetic line weighed significantly less than RHA control progeny (pd 35-44); however, SHS progeny from the low-dose group weighed significantly more than progeny from any other group (pd 14-44). Unconditioned escape response (UER) level was determined on pd 39. Progeny from the high-dose group required a significantly lower UER level as compared to the low-dose group. Acquisition of conditioned avoidance responses was tested from pd 41 to 44. There were significant differences due to dose for one-way avoidance responses. Cd-related differences in one-way avoidance were restricted to progeny from the SHS genetic line. SHS progeny from the high-dose group demonstrated significantly more one-way responses when compared to the control group. Differences in avoidance responses are discussed in relation to Cd-induced hypernociception. The concentration of Cd in the liver and kidney of dams and progeny was determined by Inductively Coupled Plasma spectroscopy (ICP). There were significant dose-related differences in Cd concentration in maternal tissues.
Pelletier
M R
MR
Lakehead University, Department of Psychology, Thunder Bay, Ontario, Canada.
Satinder
K P
KP
D000818:Animals; D001362:Avoidance Learning / Q000187:drug effects*; D001835:Body Weight / Q000187:drug effects; D002104:Cadmium / Q000633:toxicity*; D019256:Cadmium Chloride; D003216:Conditioning, Operant; D005260:Female; D006128:Growth / Q000187:drug effects; D008098:Litter Size / Q000187:drug effects; D009043:Motor Activity / Q000187:drug effects*; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects; D051381:Rats; D011919:Rats, Inbred Strains; D012018:Reflex / Q000187:drug effects
D002104:Cadmium; D019256:Cadmium Chloride