OBJECTIVE Postmortem studies have implicated the central muscarinic acetylcholine system in schizophrenia. However, central muscarinic receptor availability has not previously been studied in vivo. Using [I-123]iodoquinuclidinyl benzilate ([(123)I]IQNB) single photon emission computed tomography (SPECT), the authors sought to compare the muscarinic receptor availability in vivo in unmedicated p...

The protective roles of Ca channel blockers against ischemic hippocampal damage are still debated. We used autoradiography to study postischemic L-type Ca channels (1,4dihydropyridine Ca channel blocker binding), adenosine A, receptors, and muscarinic chollnergic receptors in the rat hippocampus using [H]PN200-110 (PN), [H]cyclohexyladenosine (CHA), and [H]quinuclidinyl benzilate (QNB), respect...

A technique was developed to evaluate the potency of ligand binding at M2 ACh receptors and to experimentally localize the M1 and M2 subtypes to specific neuronal processes. Normal and experimental material was prepared with tritiated ligand binding to cryostat-sectioned area 29c of posterior cingulate cortex in rat, coverslip autoradiography, and single-grain-counting techniques. Three fundame...

A procedure was developed for the large scale preparation of membranes from pig atria which are enriched 10-13 fold in the muscarinic acetylcholine receptor. The procedure involved differential centrifugation and sucrose-gradient centrifugation in solutions containing 150 mM-NaClO4 and 5 mM-EDTA to minimize membrane aggregation. The final membrane preparation bound about 1.1 pmol of L-quinuclid...

The neurochemical effects in developing rats exposed during gestation to the anticholinesterase organophosphorus insecticide chlorpyrifos (CPS) were determined. Pregnant rats were dosed daily with CPS (0, 3, or 7 mg/kg) in corn oil from gestation days (GD) 6-20. Pups were euthanized on postnatal days (PND) 1, 3, 6, 9, 12, and 30 for the determination of brain cholinesterase (ChE) and choline ac...

We investigated the properties and interaction domains of SN-6 [2-[4-(4-nitrobenzyloxy)benzyl]thiazolidine-4-carboxylic acid ethyl ester], a newly synthesized and selective Na /Ca exchange (NCX) inhibitor. SN-6 (0.3–30 M) inhibited preferentially intracellular Na -dependent Ca uptake (i.e., the reverse mode) compared with extracellular Na -dependent Ca efflux (i.e., the forward mode) in NCX1-tr...