Forebrain ischemia induces selective behavioral impairments associated with hippocampal injury in rats.

Abstract

Two groups of rats were tested on a variety of motor and cognitive tasks after either 10 minutes of two-vessel occlusion forebrain ischemia (n=8) or sham operative procedures (n=6). Histological injury was absent in the sham-operated group. In the ischemic group, hippocampal injury was restricted to field CA1, while damage in the neocortex and caudoputamen was sparse. Motor tests performed on postoperative days 18 and 28 revealed no significant differences between the ischemic and sham-operated groups. Retention performance of a radial maze discrimination task was impaired, with a significant but transient increase in both working and reference memory errors. Passive avoidance acquisition and retention were not significantly affected, although conclusions concerning the utility of this task must be reserved because of variability in the behavior of the sham-operated rats. Morris maze spatial navigation (place learning) and open-field activity were insensitive to treatment group. These functional results are consistent with the observed histological injury and what is known about hippocampal injury and behavior, and they provide further guidance for the development of neurological assays appropriate for discriminating outcome from forebrain ischemia in rats.

Neuroprotection from Delayed Postischemic Administration of a Metalloporphyrin Catalytic Antioxidant

“…On the fifth postoperative day, with the observer blinded to group assignment, motor f unction tests were performed according to an established protocol, including assays of prehensile traction and balance beam performance (Combs and D'Alecy, 1987;Gionet et al, 1991). The motor score was graded on a 0 -9 scale (best score ϭ 9).…”

Effects of a Synthetic Allosteric Modifier of Hemoglobin Oxygen Affinity on Outcome From Global Cerebral Ischemia in the Rat

“…13,14 The motor score was graded on a scale of 0 to 9 (best scoreϭ9). Rats were then anesthetized with halothane and underwent in situ brain fixation by intracardiac injection of buffered 4% formalin.…”

A novel version of the 8-arm radial maze: effects of cerebral ischemia on learning and memory

“…The nature of cognitive disturbances following cerebral ischemia has been widely studied in the rat. In this species, three behavioral models of spatial learning and memory have been frequently used: the Morris water maze (Auer et al, 1989;Gionet et al, 1991;Hagan and Beaughard, 1990;Jaspers et al, 1990;Kiyota et al, 1991;Rod et al, 1990), the 8-arm radial maze (Davis et al, 1986;Gionet et al, 1991;Kiyota et al, 1991;Okada et al, 1995;Volpe et al, 1984), and the delayed, non-matching to sample (DNMS) paradigm (Volpe et al, 1992;Wood et al, 1993); for review see .…”