Red blood cell ionized calcium concentration in spontaneous hypertension: modulation in vivo by the calcium antagonist PN 200.110.
1. Altered calcium regulation has been observed in experimental and human hypertension. In this study erythrocyte (RBC) intracellular calcium concentration ([Ca2+]i) was compared in conscious spontaneously hypertensive rats (SHR) and their normotensive controls (WKY) at rest and after injection of the dihydropyridine calcium antagonist PN 200.110. 2. Resting [Ca2+]i was similar in SHR and WKY. 3. PN 200.110 administration induced a rapid decrease in blood pressure in SHR and WKY. Five minutes after the injection no change in [Ca2+]i was observed; at 1 h [Ca2+]i was significantly decreased in SHR, but not in WKY. 4. These results suggest that the mutual adaptation of the rate of calcium influx through calcium channels and the activity of the calcium extruding pump differ between WKY and SHR.
Morris
M J
MJ
INSERM U7, Hôpital Necker, Paris, France.
David-Dufilho
M
M
Devynck
M A
MA
D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D002118:Calcium / Q000097:blood*; D002121:Calcium Channel Blockers / Q000494:pharmacology*; D004912:Erythrocytes / Q000187:drug effects / Q000378:metabolism*; D006973:Hypertension / Q000097:blood*; D066298:In Vitro Techniques; D017275:Isradipine; D008297:Male; D010069:Oxadiazoles / Q000494:pharmacology*; D051381:Rats; D011918:Rats, Inbred SHR; D011921:Rats, Inbred WKY
D002121:Calcium Channel Blockers; D010069:Oxadiazoles; D002118:Calcium; D017275:Isradipine