Isoenzyme profile of lactate dehydrogenase in the cranial cervical sympathetic ganglion under normal conditions and during synaptic blockade.
The isoenzyme profile of lactate dehydrogenase in the cranial cervical sympathetic ganglion of rabbits was studied under normal conditions and during blockade of nicotinic cholinergic synapses. Under normal conditions this profile was presented by 5 isoforms of the enzyme (lactate dehydrogenases 1, 2, 3, 4, and 5). Activity of H-isoforms prevailed. Blockade was accompanied by heterotropic allosteric inhibition of lactate dehydrogenase isoforms. H- and M-isoforms underwent simultaneous changes. Activity of H-isoforms sharply decreased. However, the ratio between lactate dehydrogenases 1 and 2 during complete or partial blockade did not differ from that observed in experiments with the intact ganglion. M-isoforms (lactate dehydrogenases 4 and 5) disappeared during partial blockade. Activity of hybrid lactate dehydrogenase 3 significantly decreased and was undetected during partial and complete blockade, respectively. Our results indicate that enzyme activity and isoenzyme profile of lactate dehydrogenase are determined by function of nicotinic synapses.
Gorelikov
P L
PL
Institute of Human Morphology, Russian Academy of Medical Sciences, Moscow.
Savelev
S V
SV
D000818:Animals; D007527:Isoenzymes / Q000096:biosynthesis; D007770:L-Lactate Dehydrogenase / Q000096:biosynthesis / Q000737:chemistry* / Q000378:metabolism; D000080864:Lactate Dehydrogenase 5; D018722:Nicotinic Agonists / Q000378:metabolism*; D010875:Pipecolic Acids / Q000494:pharmacology; D020033:Protein Isoforms; D011817:Rabbits; D017783:Superior Cervical Ganglion / Q000201:enzymology*; D013569:Synapses / Q000378:metabolism / Q000473:pathology; D009435:Synaptic Transmission / Q000187:drug effects
D007527:Isoenzymes; D018722:Nicotinic Agonists; D010875:Pipecolic Acids; D020033:Protein Isoforms; C010927:dimecolin; D007770:L-Lactate Dehydrogenase; C409676:lactate dehydrogenase 2; C409677:lactate dehydrogenase 3; C409678:lactate dehydrogenase 4; D000080864:Lactate Dehydrogenase 5; C409667:lactate dehydrogenase 1