Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0023380 (lethargy)
 5,697 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A protein toxic to mice was isolated from the venom of the Mexican beaded lizard Heloderma horridum horridum by a combination of gel filtration (Sephadex G-75) and ion exchange chromatography (both diethylaminoethyl-cellulose [DE-cellulose] and carboxymethyl-cellulose [CM-cellulose]). The purified polypeptide component has an apparent mol. wt of 25,500 and is composed of approximately 220 amino acid residues. It has an isoelectric point (pI) of 6.8 and its N-terminal amino acid sequence was shown to be: Glu-Ala-Ser-Pro-Lys-Leu-Pro-Gly-Leu-Met-Thr-Ser-Asn-Pro-Asp-Gln-Gln-Thr- Glu-Ile. The sequence has no significant similarity with any other protein previously reported in the literature. Enzymatic activities such as phospholipase, hyaluronidase and proteinase, commonly present in venoms, could not be demonstrated in this protein. Patch-clamp experiments conducted with excitable membranes show no effects on Na+, K+ or Ca2+ ion channels. Among the constant physiological effects observed in mice injected with this toxin are lethargy, partial paralysis of rear limbs and lowering of body temperature, suggesting that it might be a hypothermic toxin. We propose calling this toxin Helothermine.
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PMID:Isolation and characterization of helothermine, a novel toxin from Heloderma horridum horridum (Mexican beaded lizard) venom. 169 19

The effects of insulin-induced hypoglycemic stupor and subsequent treatment with glucose on mouse cerebral cortical, cerebellar and brain stem levels of glucose, glycogen, ATP, phosphocreatine, glutamate, aspartate and GABA and on cerebral cortical and cerebellar levels of cyclic AMP and cyclic GMP have been measured. Hypoglycemia decreased glucose, glycogen and glutamate levels and had no effect on ATP levels in all three regions of brain. GABA levels were decreased only in cerebellum. Aspartate levels rose in cerebral cortex and brain stem, and creatine phosphate increased in cerebral cortex and cerebellum. In the hypoglycemic stuporous animals, cyclic GMP levels were elevated in cerebral cortex and depressed in cerebellum whereas cyclic AMP levels were unchanged from control values. Intravenous administration of 2.5-3.5 mmol/kg of glucose to the hypoglycemic stuporous animals produced recovery of near normal neurological function within 45 s. Only brain glucose and aspartate levels returned to normal prior to behavioral recovery. These results suggest that of the several substances examined in this study, only glucose and perhaps aspartate have important roles in the biochemical mechanisms producing neurological abnormalities in hypoglycemic animals.
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PMID:Regional levels of glucose, amino acids, high energy phosphates, and cyclic nucleotides in the central nervous system during hypoglycemic stupor and behavioral recovery. 1217 May 86