Olfactory deprivation increases dopamine D2 receptor density in the rat olfactory bulb

Journal Article · Wed May 01 00:00:00 EDT 1991 · Synapse (New York); (United States)

DOI:https://doi.org/10.1002/syn.890080109· OSTI ID:5266500

Guthrie, K M; Pullara, J M; Marshall, J F; Leon, M ^[1]

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1. University of California, Irvine (USA)

Unilateral olfactory deprivation during postnatal development results in significant anatomical and neurochemical changes in the deprived olfactory bulb. Perhaps the most dramatic neurochemical change is the loss of dopaminergic expression by neurons of the glomerular region. The authors describe here the effects of early olfactory deprivation on other elements of the bulb dopaminergic system, namely the dopamine receptors of the olfactory bulb. Rat pups had a single naris occluded on postnatal day 2 (PN2). On PN20 or PN60, animals were sacrificed and the bulbs were examined for catecholamine levels or D2 and D1 dopamine receptor binding. Receptor densities were quantified by in vitro autoradiography using the tritiated antagonists spiperone (D2) and SCH23390 (D1). Dopamine uptake sites were similarly examined using tritiated mazindol. No significant specific labeling of D1 or mazindol sites was observed in the olfactory bulbs of control or experimental animals at either age. Normal animals displayed prominent labeling of D2 sites in the glomerular and nerve layers. After 60 days of deprivation, deprived bulbs exhibited an average increase in D2 receptor density of 32%. As determined by Scatchard analysis, the mean values for Kd and Bmax were 0.134 nM and 293 fmol/mg protein in normal bulbs, and 0.136 nM and 403 fmol/mg protein in deprived bulbs. The results suggest that, as in the neostriatum, dopamine depletion in the olfactory bulb leads to an upregulation of D2 receptor sites. This change may represent an attempt by the system to adapt neurochemically to reduced dopaminergic activity and thereby maintain bulb function.

• OSTI ID: 5266500
• Journal Information: Synapse (New York); (United States), Journal Name: Synapse (New York); (United States) Vol. 8:1; ISSN 0887-4476; ISSN SYNAE
• Country of Publication: United States
• Language: English

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59 BASIC BIOLOGICAL SCIENCES
AMINES
ANIMAL CELLS
ANIMALS
AROMATICS
AUTONOMIC NERVOUS SYSTEM AGENTS
AUTORADIOGRAPHY
BIOCHEMICAL REACTION KINETICS
BIOCHEMISTRY
BODY
BRAIN
CARDIOTONICS
CARDIOVASCULAR AGENTS
CATECHOLAMINES
CENTRAL NERVOUS SYSTEM
CHEMISTRY
DOPAMINE
DRUGS
HYDROGEN COMPOUNDS
HYDROXY COMPOUNDS
KINETICS
MAMMALS
MEMBRANE PROTEINS
NERVE CELLS
NERVOUS SYSTEM
NEUROREGULATORS
OLFACTORY BULBS
ORGANIC COMPOUNDS
ORGANS
PHENOLS
POLYPHENOLS
PROTEINS
RATS
REACTION KINETICS
RECEPTORS
RODENTS
SOMATIC CELLS
SPIPERONE
SYMPATHOMIMETICS
TRITIUM COMPOUNDS
VERTEBRATES