Modulation of K+ transport across synaptosomes of rat brain by synthetic pyrethroids.
Potassium transport across synaptosomes was studied under the influence of two synthetic pyrethroids, (Permethrin, without the cyano group) and Cypermethrin (CPM, with the cyano group). Synaptosomes were isolated from rat brain cerebral cortex and incubated with 40 microM of PM and CPM for 15 min at 37 degrees C. K+ release was monitored by a K(+)-sensitive electrode. CPM caused more K+ release from synaptosomes compared to PM. K+ transport is regulated by Na(+)-K(+)-ATPase, K(+)-ATPase and K+ channels. To understand the mode of action, synaptosomes were preincubated with 9.5 x 10(-3) M ouabain (inhibitor of Na(+)-K(+)-ATPase), 1.7 x 10(-2) M N-ethylmaleamide (K(+)-ATPase inhibitor), and 9.5 x 10(-5) M quinine sulfate (K(+)-channel blocker) for 15 min at 37 degrees C. In the presence of ouabain and N-ethylmaleamide, PM- and CPM-induced K+ release was decreased and in the presence of quinine sulfate, there was no release of K+. Furthermore, the studies indicated that PM and CPM significantly decreased K+ uptake.
Rao
G V
GV
Department of Biochemistry and Nutrition, Central Food Technological Research Institute, Mysore, India.
Rao
K S
KS
D000251:Adenosine Triphosphatases / Q000037:antagonists & inhibitors; D000818:Animals; D000962:Antimalarials / Q000494:pharmacology; D001692:Biological Transport / Q000187:drug effects; D027682:Cation Transport Proteins; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005033:Ethylmaleimide / Q000494:pharmacology; D007306:Insecticides / Q000138:chemical synthesis / Q000494:pharmacology*; D008297:Male; D010042:Ouabain / Q000494:pharmacology; D026023:Permethrin; D011188:Potassium / Q000493:pharmacokinetics*; D026902:Potassium Channel Blockers; D011722:Pyrethrins / Q000138:chemical synthesis / Q000494:pharmacology*; D011803:Quinine / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D012964:Sodium / Q000378:metabolism / Q000493:pharmacokinetics; D000254:Sodium-Potassium-Exchanging ATPase / Q000037:antagonists & inhibitors; D013054:Spectrophotometry, Atomic; D013574:Synaptosomes / Q000737:chemistry / Q000187:drug effects / Q000378:metabolism*; D013997:Time Factors
D000962:Antimalarials; D027682:Cation Transport Proteins; D004791:Enzyme Inhibitors; D007306:Insecticides; D026902:Potassium Channel Blockers; D011722:Pyrethrins; C017160:cypermethrin; D026023:Permethrin; D010042:Ouabain; D012964:Sodium; D011803:Quinine; D000251:Adenosine Triphosphatases; C022761:potassium transporting ATPase; D000254:Sodium-Potassium-Exchanging ATPase; D005033:Ethylmaleimide; D011188:Potassium