Inhibitory effect of intrahippocampal NPY injection on amphetamine-induced behavioural activity.
The aim of the present study was to investigate the influence of intrahippocampal neuropeptide Y (NPY) administration on the rats' behaviour. The CA1 field or dentate area (GD) of the dorsal hippocampus was chronically implanted with intracerebral cannulae. NPY (or redistilled water in the control group) was injected bilaterally or unilaterally in a volume of 1 microliter to each hippocampus, in a dose of 1 or 2 micrograms per rat. A separate group of rats was pretreated with amphetamine (1 mg/kg, s.c.), 15 min before a bilateral microinjection of NPY (2 micrograms) into the CA1 region. Immediately after the intrahippocampal injection, the rats' behaviour was tested in an open field box. It was found that NPY did not change the locomotor and the exploratory activity after either CA1 or GD administration to non-pretreated animals. In amphetamine pretreated rats, NPY injected into the CA1 field inhibited the amphetamine induced increase in sniffing and rearing and, to a lesser extent, the number of line-crossings. The obtained results may suggest an inhibitory action of NPY in the CA1 hippocampal field on the behavioural hyperactivity.
Smiałowska
M
M
Department of Neurobiology, Polish Academy of Sciences, Kraków, Poland.
Sopala
M
M
Tokarski
K
K
D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects*; D000697:Central Nervous System Stimulants / Q000037:antagonists & inhibitors* / Q000494:pharmacology; D003913:Dextroamphetamine / Q000037:antagonists & inhibitors* / Q000494:pharmacology; D005106:Exploratory Behavior / Q000187:drug effects; D006624:Hippocampus / Q000502:physiology*; D007279:Injections, Subcutaneous; D008297:Male; D008845:Microinjections; D009043:Motor Activity / Q000187:drug effects; D009478:Neuropeptide Y / Q000008:administration & dosage / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar
D000697:Central Nervous System Stimulants; D009478:Neuropeptide Y; D003913:Dextroamphetamine