Abnormality in sarcoplasmic reticulum-dependent arterial contraction in responses to caffeine and noradrenaline in spontaneously hypertensive rats.

We studied caffeine- and noradrenaline-induced contraction in tail arteries from 4-week-old male SHR and age- and sex-matched WKY. After the sarcoplasmic reticulum Ca2+ had been depleted by the Ca(2+)-free EGTA (0.1 mmol/l) solution, the caffeine (10 mmol/l)-induced contractions in a low-Ca2+ (0.5 mmol/l) solution were smaller in SHR than in WKY. After the… (More)