Hippocampal corticosterone receptors and novelty-induced behavioral activity : effect of kainic acid lesion in the hippocampus

摘要: Rats were injected bilaterally in the dorsal and ventral hippocampus with kainic acid (KA) or artificial CSF their behavior brain corticosterone (B) receptor systems studied. The hippocampal KA injection destroyed part of pyramidal neurons dentate gyrus neurons. These contain a system for B. At 2 weeks after lesion this B displays an increase apparent maximal binding capacity (Bmax) approximately 25%. compensatory concentration is reflected increased uptake [3H]B cell nuclei slices incubated vitro saturating concentrations steroid. Administration tracer dose shows that labelled steroid can enter vivo nuclear compartment KA-lesioned lobe. role was investigated on novelty-induced behavioral activities sham-lesioned animals large open small closed field at 10 days bilateral adrenalectomy (ADX) sham-ADX which 14 (sham) lesion. (300 micrograms/kg rat) administered s.c. 1 h prior to test. resulted exploratory activity reduction grooming immobility. After ADX effect exploration reduced 5 min abolished 30 field. displayed more (closed-field). replacement rats reinstated hyperactivity rats. On some components such as ambulation open-field locomotion field, there even larger responsiveness than control animals. It concluded (1) containing neurons, remaining tissue number sites; (2) required full expression without lesions; (3) display B; (4) sites may underlie