Age differences in acquisition and retention of one-way avoidance learning in C57BL/6NNia and autoimmune mice.
Acquisition and 48-h retention of a step-up active avoidance response were studied in separate age groups of C57BL/6NNia mice (aged 1.5, 3.5, 6, 12, or 26 months) and five strains of genetically autoimmune mice differing in life span. The C57BL/6NNia mice showed no change in ability to acquire the avoidance response between 1.5 and 3.5 months, but showed a steady decline in that ability thereafter. Mouse strains with early-onset autoimmune disorder (NZB/B1NJ, MRL/MpJ-lpr, and BXSB/MpJ) showed declines in acquisition capability between 1.5 and 3.5 months of age, whereas mouse strains with mild, late-onset autoimmune disorder (MRL/MpJ- + and NZBWF1/J) showed stable or improved acquisition during that period. Both the C57BL/6NNia and NZB/B1NJ mice showed age-dependent declines in 48-h retention performance by 12 months of age. These findings suggested that while 48-h retention performance deficits were most related to chronological age, avoidance acquisition deficits were related to development of autoimmunity.
Forster
M J
MJ
Department of Pharmacology, Texas College of Osteopathic Medicine, Fort Worth 76107-2690.
Popper
M D
MD
Retz
K C
KC
Lal
H
H
D000375:Aging / Q000502:physiology*; D000818:Animals; D001327:Autoimmune Diseases / Q000503:physiopathology*; D001362:Avoidance Learning / Q000502:physiology*; D008297:Male; D008568:Memory / Q000502:physiology*; D051379:Mice; D008810:Mice, Inbred C57BL; D008815:Mice, Inbred Strains; D008817:Mice, Mutant Strains / Q000502:physiology*; D011930:Reaction Time / Q000502:physiology; D012153:Retention, Psychology / Q000502:physiology*