Cyclic AMP metabolism in fragile X syndrome.
Cyclic AMP (cAMP) metabolism was studied in platelets from a series of 14 patients with fragile X syndrome (fra X) and 21 control individuals. 1-Isobutyl-3-methylxanthine was used to inhibit phosphodiesterase and thus measure cAMP production, prostaglandin E1 was used to assess receptor-mediated cAMP accumulation, and forskolin was used to directly stimulate the catalytic subunit. In patients with fra X, basal production was 63% of that of control subjects (p = 0.019). Prostaglandin E1- and forskolin-stimulated production were 61% (p = 0.039) and 56% (p = 0.012) of that of control subjects, respectively. cAMP production in 8 patients with fra X overlapped the control range, whereas measures of production in 6 patients formed a cluster with values lower than any of the 21 control subjects assayed, suggesting possible biochemical heterogeneity within patients with fra X. Results obtained from the group of patients with fra X suggest possible abnormal function or regulation of the catalytic subunit of adenylate cyclase in at least a subgroup of patients with fra X. Variability of biochemical findings in patients with fra X may reflect the known high variability of the clinical syndrome.
Department of Pediatrics, University of Chicago, IL.
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Berry-Kravis
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Huttenlocher
D015056:1-Methyl-3-isobutylxanthine / Q000494:pharmacology; D000293:Adolescent; D000328:Adult; D000527:Alprostadil / Q000494:pharmacology; D001792:Blood Platelets / Q000187:drug effects / Q000378:metabolism*; D002648:Child; D002675:Child, Preschool; D005576:Colforsin / Q000494:pharmacology; D000242:Cyclic AMP / Q000378:metabolism*; D005260:Female; D005600:Fragile X Syndrome / Q000150:complications / Q000378:metabolism* / Q000523:psychology; D006801:Humans; D008607:Intellectual Disability / Q000209:etiology / Q000378:metabolism; D007858:Learning / Q000502:physiology; D008297:Male; D008570:Memory, Short-Term / Q000502:physiology; D008875:Middle Aged; D015290:Second Messenger Systems
D005576:Colforsin; D000242:Cyclic AMP; D000527:Alprostadil; D015056:1-Methyl-3-isobutylxanthine