Effects of septal grafts on acetylcholine release from rat hippocampus after 192 IgG-saporin lesion.
The cholinergic inputs to the rat hippocampus were lesioned by intraseptal injections of 192 IgG-saporin. After 15 days, fetal septal cells were grafted into the hippocampus. Thirteen months later, hippocampal acetylcholine (ACh) release was studied by microdialysis. Lesioning reduced basal ACh release (100%) to 20% of normal, which was compensated for by the graft (71%). Infusion of the serotonin uptake inhibitor citalopram (100 microM) enhanced ACh release to the same extent (% of basal release) in all rat groups. Systemic injection of 8-OH-DPAT (0.5 mg/kg, SC), an agonist of 5-HT1A receptors, caused a smaller ACh release than citalopram. Acetylcholinesterase (AChE) staining and densitometric quantification revealed that the lesion-induced reduction of the AChE-staining density was compensated for by septal grafting. In conclusion, both histochemical and biochemical methods showed that cholinergic hippocampal parameters were drastically impaired by 192 IgG-saporin lesions, but were almost completely restored by septal grafting. The graft responded to intrinsic serotonergic regulation.
Hilgert
Michael
M
Department of Pharmacology, University of Mainz, Obere Zahlbacher Str. 67, D-55101 Mainz, Germany.
Hartmann
Joachim
J
Löffelholz
Konrad
K
Jeltsch
Hélène
H
Cassel
Jean-Christophe
JC
Klein
Jochen
J
D000109:Acetylcholine / Q000378:metabolism*; D000110:Acetylcholinesterase / Q000378:metabolism; D000818:Animals; D000911:Antibodies, Monoclonal; D001927:Brain Diseases / Q000139:chemically induced / Q000601:surgery*; D018678:Cholinergic Agents; D006624:Hippocampus / Q000378:metabolism* / Q000601:surgery*; D000922:Immunotoxins; D008297:Male; D009699:N-Glycosyl Hydrolases; D051381:Rats; D020318:Rats, Long-Evans; D054789:Ribosome Inactivating Proteins, Type 1; D000076985:Saporins; D012688:Septum Pellucidum / Q000637:transplantation*; D012701:Serotonin / Q000378:metabolism
C085696:192 IgG-saporin; D000911:Antibodies, Monoclonal; D018678:Cholinergic Agents; D000922:Immunotoxins; D054789:Ribosome Inactivating Proteins, Type 1; D012701:Serotonin; D000110:Acetylcholinesterase; D009699:N-Glycosyl Hydrolases; D000076985:Saporins; D000109:Acetylcholine