title: Effects of microgravity on brain neurotransmitter receptors.
abstract: Neurotransmitter receptor binding and Na+, K+-ATPase activity were examined in the brains of six rats exposed to 7 days of microgravity during the flight of Spacelab 3. The same variables were examined in a group of six ground control rats. 5-HT1 receptor number in the hippocampus was significantly elevated by exposure to the microgravity environment, and cortical sodium-potassium pump activity was significantly depressed. A marginal depression in dopamine D-2 binding in the striatum was noted. Dopamine and 5-HT binding in a wide variety of other central regions, in addition to GABAA, muscarinic acetylcholine, adenosine A1, and opiate receptor binding, and adrenoceptor binding, was unaffected by microgravity exposure.
authors.affiliation: Department of Animal Physiology, University of California, Davis 95616.
authors.forename: J D
authors.initials: JD
authors.lastname: Miller
authors.forename: B A
authors.initials: BA
authors.lastname: McMillen
authors.forename: M M
authors.initials: MM
authors.lastname: McConnaughey
authors.forename: H L
authors.initials: HL
authors.lastname: Williams
authors.forename: C A
authors.initials: CA
authors.lastname: Fuller
mesh_terms: D000818:Animals; D001921:Brain / Q000201:enzymology; D001923:Brain Chemistry; D006112:Gravitation; D066298:In Vitro Techniques; D008297:Male; D011869:Radioligand Assay; D051381:Rats; D011919:Rats, Inbred Strains; D011954:Receptors, Dopamine / Q000378:metabolism; D017981:Receptors, Neurotransmitter / Q000378:metabolism*; D000254:Sodium-Potassium-Exchanging ATPase / Q000378:metabolism
chemical_list: D011954:Receptors, Dopamine; D017981:Receptors, Neurotransmitter; D000254:Sodium-Potassium-Exchanging ATPase