Korean J Physiol Pharmacol.
1997 Dec;1(6):657-664.
Effect of adenosine on the release of (3H)-5-hydroxytryptamine during
glucose/oxygen deprivation from rat hippocampal slices
- Affiliations
-
- 1Department of Pharmacology, Ewha Womans University, College of Medicine, Seoul 158-056, South Korea.
Abstract
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The effects of adenosine, adenosine A1 receptor antagonist (DPCPX), or
NMDA receptor antagonist (APV) on the spontaneous release of
(3H)-5-hydroxytryptamine ((3H)-5-HT) during normoxic/normoglycemic or
hypoxic/hypoglycemic period were studied in the rat hippocampal slices.
The hippocampus was obtained from the rat brain and sliced 400 mum
thickness with the tissue slicer. After 30 min's preincubation in the
normal buffer, the slices were incubated for 30 min in a buffer
containing (3H)-5-HT (0.1 muM, 74 muCi/8 ml) for uptake, and washed. To
measure the release of (3H)-5-HT into the buffer, the incubation medium
was drained off and refilled every ten minutes through sequence of 14
tubes. Induction of glucose/oxygen deprivation (GOD; medium depleting
glucose and gassed with 95% N2/5% CO2) was done in 6th and 7th tube.
The radioactivities in each buffer and the tissue were counted using
liquid scintillation counter and the results were expressed as a
percentage of the total radioactivities. When slices were exposed to
GOD for 20 mins, the spontaneous release of (3H)-5-HT was markedly
increased and this increase of (3H)-5-HT release was blocked by
adenosine (10 muM) or DL-2-amino-5-phosphonovaleric acid (APV; 30 muM).
Adenosine A1 receptor specific antagonist,
8-cyclopentyl-1,3-dipropylxanthine (DPCPX) exacerbate GOD-induced
increase of spontaneous release of (3H)-5-HT. These results suggest
that Adenosine may play a role in the GOD-induced spontaneous release
of (3H)-5-HT through adenosine A1 receptor activity.