The influence of amlodipine and verapamil on ion and water transport in the nephron, skin and urinary bladder of amphibians.
1. The addition of amlodipine or verapamil into the lumen of the newt distal tubule led to the decrease of reabsorption of Na, Cl, Ca and of fluid. 2. The application of amlodipine to the outside of the frog skin caused large increases in potential difference (PD) and short circuit (SCC) similar to what is seen with Co2+. If both amlodipine and Co2+ were applied simultaneously to the outer surface the increases in PD and SCC were additive. 3. Verapamil added to the outer surface of the skin caused a reduction in PD which could be overcome by subsequent addition of amlodipine. 4. After addition of amlodipine to serosal or mucosal surfaces of the frog urinary bladder, the ability of vasopressin to increase osmotic permeability was markedly attenuated. 5. It is likely that the calcium channel blockers used here not only affect intracellular calcium levels by inhibiting entry through calcium channels, but they may also alter calcium dependent processes within the plasma membranes which modulate sodium transfer across epithelia.
Sechenov Institute of Evolutionary Physiology and Biochemistry, Leningrad, U.S.S.R.
Natochin YuV
O A
OA
Goncharevskaya
E J
EJ
Johns
Monin YuG
E I
EI
Shakhmatova
D017311:Amlodipine; D000818:Animals; D002196:Capillaries / Q000502:physiology; D007668:Kidney / Q000187:drug effects / Q000378:metabolism; D007684:Kidney Tubules / Q000098:blood supply / Q000187:drug effects / Q000378:metabolism; D008297:Male; D009399:Nephrons / Q000378:metabolism*; D009543:Nifedipine / Q000031:analogs & derivatives* / Q000494:pharmacology; D010477:Perfusion; D011896:Rana temporaria; D012455:Salamandridae; D012867:Skin / Q000378:metabolism*; D012964:Sodium / Q000378:metabolism*; D001743:Urinary Bladder / Q000378:metabolism*; D014667:Vasopressins / Q000494:pharmacology; D014700:Verapamil / Q000494:pharmacology*; D014867:Water / Q000378:metabolism*
D014867:Water; D014667:Vasopressins; D017311:Amlodipine; D012964:Sodium; D014700:Verapamil; D009543:Nifedipine