Moderate impairment of learning and memory has been recognized as a complication of diabetes. The present study examined behavioral and electrophysiological measures of cerebral function in streptozotocin (STZ)-induced diabetic rats. Behavioral testing consisted of a spatial learning task in a water maze. Electrophysiological testing consisted of in vitro assessment of hippocampal long-term potentiation (LTP), an activity-dependent form of synaptic plasticity, which is believed to be related to the cellular mechanisms of learning and memory. Two experiments were performed: the first with severely hyperglycemic rats and the second with moderately hyperglycemic rats. Rats were tested in the water maze 11 weeks after induction of diabetes. Next, LTP was measured in vitro in trained animals. Both spatial learning and LTP expression in the CA1 field of the hippocampus were impaired in severely hyperglycemic rats as compared with nondiabetic controls. In contrast, spatial learning and hippocampal LTP were unaffected in moderately hyperglycemic rats. The association of alterations in hippocampal LTP with specific learning impairments has previously been reported in conditions other than diabetes. Our findings suggest that changes in LTP-like forms of synaptic plasticity in the hippocampus, and possibly in other cerebral structures, are involved in learning deficits in STZ-induced diabetes. The beneficial effect of moderate glycemic control on both place learning and hippocampal LTP supports the significance of the relation between these two parameters and indicates that the development of the observed deficits may be related to the level of glycemic control.
Skip Nav Destination
Article navigation
Original Articles|
September 01 1996
Place Learning and Hippocampal Synaptic Plasticity in Streptozotocin-Induced Diabetic Rats
Geert-Jan Biessels;
Geert-Jan Biessels
Department of Internal Medicine, Academic Hospital Utrecht
The Netherlands
Search for other works by this author on:
Amer Kamal;
Amer Kamal
Rudolf Magnus Institute for Neurosciences, Department of Medical Pharmacology
Utrecht
Search for other works by this author on:
Geert M Ramakers;
Geert M Ramakers
Rudolf Magnus Institute for Neurosciences, Department of Medical Pharmacology
Utrecht
Search for other works by this author on:
Ivan J Urban;
Ivan J Urban
Rudolf Magnus Institute for Neurosciences, Department of Medical Pharmacology
Utrecht
Search for other works by this author on:
Berrie M Spruijt;
Berrie M Spruijt
Rudolf Magnus Institute for Neurosciences, Department of Medical Pharmacology
Utrecht
Search for other works by this author on:
D Willem Erkelens;
D Willem Erkelens
Department of Internal Medicine, Academic Hospital Utrecht
The Netherlands
Search for other works by this author on:
Willem Hendrik Gispen
Willem Hendrik Gispen
Rudolf Magnus Institute for Neurosciences, Department of Medical Pharmacology
Utrecht
Search for other works by this author on:
Address correspondence and reprint requests to Dr. Michael R. Christie, Department of Medicine, King's College School of Medicine and Dentistry, Bessemer Rd., London SE5 9PJ, U.K.
Diabetes 1996;45(9):1259–1266
Article history
Received:
November 14 1995
Revision Received:
April 18 1996
Accepted:
April 18 1996
PubMed:
8772732
Citation
Geert-Jan Biessels, Amer Kamal, Geert M Ramakers, Ivan J Urban, Berrie M Spruijt, D Willem Erkelens, Willem Hendrik Gispen; Place Learning and Hippocampal Synaptic Plasticity in Streptozotocin-Induced Diabetic Rats. Diabetes 1 September 1996; 45 (9): 1259–1266. https://doi.org/10.2337/diab.45.9.1259
Download citation file:
226
Views