Glibenclamid-sensitive K+ channels are responsible for angiotensin II hypersensitive contraction and atrial natriuretic factor refractoriness of glomeruli in low-sodium rats.
We investigated the role of ANF and potassium channels in dynamics of glomeruli isolated from low and normal-sodium rats. The ANG II-induced decrease glomerular size (36%) and (18%) in low and normal-sodium rats, respectively. ANF or cicletanine showed reversing effect on the ANG II-precontracted glomeruli from normal but not from low-sodium rats. The action of ANG II was abolished when ANF and cicletanine were added together. Glibenclamid completely abolished the inhibitory effect of cicletanine and ANF on ANG II-induced contraction of glomeruli from low-sodium rats. These results suggest that glibenclamid-sensitive potassium channels are responsible for ANG II hypersensitive contraction and ANF or cicletanine refractoriness of isolated glomeruli from low-sodium rats.
Szczepańska-Konkel
M
M
Department of Clinical Biochemistry, Medical Academy, Gdańsk, Poland.
Redlak
M
M
Angielski
S
S
D000804:Angiotensin II / Q000494:pharmacology*; D000818:Animals; D009320:Atrial Natriuretic Factor / Q000494:pharmacology*; D002196:Capillaries / Q000187:drug effects / Q000502:physiology; D004232:Diuretics / Q000494:pharmacology; D005905:Glyburide / Q000494:pharmacology*; D007444:Inulin; D007678:Kidney Glomerulus / Q000098:blood supply*; D007700:Kinetics; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects; D009131:Muscle, Smooth, Vascular / Q000187:drug effects / Q000502:physiology; D015221:Potassium Channels / Q000187:drug effects / Q000502:physiology*; D011725:Pyridines; D051381:Rats; D011919:Rats, Inbred Strains; D014661:Vasoconstriction / Q000187:drug effects*
D004232:Diuretics; D015221:Potassium Channels; D011725:Pyridines; D000804:Angiotensin II; D009320:Atrial Natriuretic Factor; D007444:Inulin; C038068:cicletanine; D005905:Glyburide