Cocaine is one of the major drugs of abuse in the U.S., and its use is still on the rise. The drug is taken for its strong central stimulant action, an effect that is believed to result from the interaction of cocaine with specific sites on nerve cells that are putatively termed """"""""cocaine receptors."""""""" The long term objective of this research is to identify the physiologic role of the cocaine receptor in mammalian brain, to understand its structure and to determine what changes occur in numbers of receptors upon chronic cocaine administration. This would shed light on the causes of the reinforcing properties of cocaine or its addiction and hopefully suggest remedial or therapeutic actions.
The specific aims are to identify the cocaine receptor in rat brain membranes, to purify it and to determine if repetitive cocaine administration causes changes in numbers of cocaine or other receptors. The hypothesis that the """"""""cocaine receptor"""""""" is a catecholamine uptake carrier will be tested, and also whether it is the carrier for one or all biogenic amines. This will be achieved by correlating the potencies of cocaine analogs and other stimulants in displacing specific H-3-cocaine binding to brain synaptosomes with their potencies in inhibiting H-3-norepinephrine, H-3-dopamine and H-3-serotonin uptake by the synaptosomes. In addition, the """"""""cocaine receptor(s)"""""""" will be purified by affinity chromatography using p-aminobenzyl cocaine as the immobilized adsorbing ligand; and purity of the isolated protein is checked with gel filtration and electrophoresis. Availability of the pure receptor will allow future studies on its structure, chemical nature and localization. The effects of repeated cocaine administration will be monitored on the numbers of receptors for cocaine, norepinephrine, dopamine and serotonin as well as biogenic amine carriers. Variations in densities of cocaine or other receptors would provide clues as to what factors may be involved in cocaine addiction and suggest possible therapy.

Agency
National Institute of Health (NIH)
Institute
National Institute on Drug Abuse (NIDA)
Type
Research Project (R01)
Project #
1R01DA003680-01A1
Application #
3208244
Study Section
(DABB)
Project Start
1985-07-01
Project End
1987-12-31
Budget Start
1985-07-01
Budget End
1985-12-31
Support Year
1
Fiscal Year
1985
Total Cost
Indirect Cost
Name
University of Maryland Baltimore
Department
Type
Schools of Medicine
DUNS #
003255213
City
Baltimore
State
MD
Country
United States
Zip Code
21201
Eshleman, A; Dunigan, C; Shamoo, A et al. (1995) ATP enhances catecholamine uptake into PC12 cells. Life Sci 56:1613-21
Eshleman, A J; Calligaro, D O; Eldefrawi, M E (1993) Allosteric regulation by sodium of the binding of [3H]cocaine and [3H]GBR 12935 to rat and bovine striata. Membr Biochem 10:129-44
el-Maghrabi, E A; Eckenhoff, R G (1993) Inhibition of dopamine transport in rat brain synaptosomes by volatile anesthetics. Anesthesiology 78:750-6
He, X; Raymon, L P; Mattson, M V et al. (1993) Further studies of the structure-activity relationships of 1-[1-(2-benzo[b]thienyl)cyclohexyl]piperidine. Synthesis and evaluation of 1-(2-benzo[b]thienyl)-N,N-dialkylcyclohexylamines at dopamine uptake and phencyclidine binding sites. J Med Chem 36:4075-81
Kline Jr, R H; Wright, J; Eshleman, A J et al. (1991) Synthesis of 3-carbamoylecgonine methyl ester analogues as inhibitors of cocaine binding and dopamine uptake. J Med Chem 34:702-5
Ahmed, M S; Zhou, D H; Maulik, D et al. (1990) Characterization of a cocaine binding protein in human placenta. Life Sci 46:553-61
Kline Jr, R H; Wright, J; Fox, K M et al. (1990) Synthesis of 3-arylecgonine analogues as inhibitors of cocaine binding and dopamine uptake. J Med Chem 33:2024-7
Cao, C J; Shamoo, A E; Eldefrawi, M E (1990) Cocaine-sensitive, ATP-dependent dopamine uptake into striatal synaptosomes. Biochem Pharmacol 39:R9-14
Cao, C J; Eldefrawi, A T; Eldefrawi, M E (1990) ATP-regulated neuronal catecholamine uptake: a new mechanism. Life Sci 47:655-67
Cao, C J; Young, M M; Wong, J B et al. (1989) Putative cocaine receptor in striatum is a glycoprotein with active thiol function. Membr Biochem 8:207-20

Showing the most recent 10 out of 13 publications