Topographical distribution of decrements and recovery in muscarinic receptors from rat brains repeatedly exposed to sublethal doses of soman. J Neurosci 1984 Aug;4(8):2069-79
Date
08/01/1984Pubmed ID
6381661Pubmed Central ID
PMC6564957DOI
10.1523/JNEUROSCI.04-08-02069.1984Scopus ID
2-s2.0-0021167068 (requires institutional sign-in at Scopus site) 40 CitationsAbstract
[3H]Quinuclidinyl benzilate binding to rat brain muscarinic receptors decreased after repeated exposure to soman, a potent organophosphorus cholinesterase inhibitor. The topographical distribution of this decrement was analyzed by quantitative receptor autoradiography. After 4 weeks of soman, three times a week, quinuclidinyl benzilate binding decreased to 67 to 80% of control in frontal and parietal cortex, caudate-putamen, lateral septum, hippocampal body, dentate gyrus, superior colliculus, nucleus of the fifth nerve, and central grey. Minor or no decreases were observed in thalamic or hypothalamic nuclei, reticular formation, pontine nuclei, inferior colliculus, nucleus of the seventh nerve, and cerebellum. Scatchard analyses of saturation curves using frontal cortex sections from soman-treated rats revealed a decrease in maximal quinuclidinyl benzilate binding from that in control rats and a return toward control levels by 24 days without any significant change in affinity. These brain areas showing significant decrements in muscarinic receptors recovered with a similar time course. An estimate of the time for 50% recovery for some of the brain areas was 14 days for superior colliculus, 16 days for cortex, and 19 days for hippocampal body. The application of quantitative receptor autoradiography to analyze receptor alterations has been valuable in localizing the telencephalon as a region more susceptible to change in receptor concentration.
Author List
Churchill L, Pazdernik TL, Jackson JL, Nelson SR, Samson FE, McDonough JH JrAuthor
Jeffrey L. Jackson MD Professor in the Medicine department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
AnimalsAutoradiography
Brain
Dose-Response Relationship, Drug
Kinetics
Organophosphorus Compounds
Quinuclidinyl Benzilate
Rats
Rats, Inbred Strains
Receptors, Muscarinic
Soman
Stereotaxic Techniques
Tissue Distribution
Tritium