PMID- 11730987
DA - 20011203
IS - 0167-0115
VI - 102
IP - 2-3
DP - 2001 Dec 15
TI - A role for the angiotensin AT(4) receptor subtype in overcoming scopolamine-induced spatial memory deficits.
PG - 147-56 AB - There is increasing interest in the role of the brain angiotensin AT(4) receptor subtype in cognitive processing. This receptor subtype is activated by angiotensin IV (AngIV), is heavily distributed in the mammalian hippocampus, neocortex, and cerebellum, and has been linked with a learning and memory function. The present investigation utilized intracerebroventricular (i.c.v.)-infused scopolamine hydrobromide (scop), a muscarinic receptor antagonist, to disrupt acquisition of the circular water maze task of spatial memory. All animals received 2 days of training trials (five trials/day) using a visible platform in an effort to preclude subsequent confounding by scopolamine-induced sensory and/or motor impairments. In the first experiment, i.c.v.-infused scopolamine (70 nmol) was followed by 0, 10, 100, or 1000 pmol i.c.v. doses of Nle(1)-AngIV in separate groups of rats. Results indicated that each dose of Nle(1)-AngIV improved the poor acquisition of this task induced by scopolamine treatment. However, the 100- and 1000-pmol doses were most effective with respect to latency and distance to find the submerged pedestal. A second experiment demonstrated that treatment with a specific AT(4) receptor antagonist, Nle(1), Leual(3)-AngIV (1000 pmol), blocked the ability of Nle(1)-AngIV (100 pmol) to improve the performance of scopolamine-compromised rats. These results support the notion that hippocampal AT(4) receptors are involved in spatial memory processing, and that activation of these binding sites can overcome the disruption of spatial memory accompanying treatment with a muscarinic receptor antagonist.
AD - Program in Neuroscience, Washington State University, 99164-6520, Pullman,
WA, USA
FAU - Pederson, E S
AU - Pederson ES
FAU - Krishnan, R
AU - Krishnan R
FAU - Harding, J W
AU - Harding JW
FAU - Wright, J W
AU - Wright JW
LA - eng
PT - Journal Article
CY - Netherlands
TA - Regul Pept
JID - 8100479
SB - IM
EDAT- 2001/12/04 10:00
MHDA- 2001/12/04 10:00
AID - S0167011501003123 [pii]
PST - ppublish
SO - Regul Pept 2001 Dec 15;102(2-3):147-56.