Intracellular free [Ca2+] in circulating lymphocytes of spontaneously hypertensive rats.
In the light of previous reports suggesting a common abnormality of Ca handling in most tissues of hypertensive humans and rats, we applied a novel technique using the fluorescent probe Quin 2 for measurement of cytosolic free Ca2+ in lymphocytes of spontaneously hypertensive rats (SHR). (Ca2+)i is increased in SHR (122.1 +/- 7.4 nM) versus normotensive Wistar-Kyoto (WKY) control rats (81.1 +/- 6.3 nM) Membrane exchange, as challenged by varying the extracellular Ca concentration over a 10(5)-fold range proved to be relatively unimportant in regulating (Ca2+)i and did not significantly affect the difference between SHR and WKY. Catecholamines and ouabain had no appreciable effect on (Ca2+)i. The mechanisms of increased (Ca2+)i in SHR lymphocytes remain to be fully elucidated.
D000818:Animals; D002118:Calcium / Q000097:blood*; D005260:Female; D006973:Hypertension / Q000097:blood*; D007545:Isoproterenol / Q000494:pharmacology; D007700:Kinetics; D008214:Lymphocytes / Q000187:drug effects / Q000378:metabolism*; D008297:Male; D009638:Norepinephrine / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains; D011922:Rats, Mutant Strains; D013045:Species Specificity
D007545:Isoproterenol; D002118:Calcium; D009638:Norepinephrine