Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0020538 (hypertension)
 170,190 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The effects of oral calcium loading on the blood pressure of spontaneously hypertensive rats (SHR) (n = 20) and age-matched normotensive Wistar-Kyoto rats (WKY) (n = 16) were investigated. Calcium loading was performed by adding 1.5% CaCl2 (Calcium chloride) to the drinking water. Calcium loading attenuated the development of hypertension in the SHR but not in the WKY, and at the end of a 3 week experiment, systolic blood pressure was 171+2 vs 197+3 mmHg (P less than 0.01). In spite of this reduction of blood pressure, there were no significant changes in sodium-water balance, plasma levels of norepinephrine and epinephrine, plasma renin activity, plasma aldosterone concentration and serum electrolytes due to the calcium treatment. On this basis, the depressor mechanism of calcium loading in the SHR was studied by observing the pressor response to norepinephrine and the vascular reactivity to norepinephrine in hind limb perfusion. It was found that both the pressor response and the vascular reactivity were significantly attenuated by the calcium treatment in the SHR but not in the WKY. These results suggest that the antihypertensive effects of calcium treatment in SHR may depend mainly on attenuation of the vascular reactivity.
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PMID:Effects of calcium loading on blood pressure in spontaneously hypertensive rats: attenuation of the vascular reactivity. 352 8

Intravenous diltiazem can be used to treat myocardial ischemia, hypertension, and supraventricular dysrhythmias, but significant adverse effects including atrioventricular block and hypotension have been reported. At the present time, there is controversy as to which drug is most effective in reversing these sequelae. This study was designed to assess the effectiveness of calcium chloride v epinephrine in reversing these side effects. The hemodynamic and electrophysiologic effects of diltiazem infusion were investigated in eight dogs anesthetized with fentanyl and nitrous oxide/oxygen. This study confirmed that diltiazem infusions in high concentrations produced predominantly atrioventricular conduction depression followed by profound hypotension. Epinephrine infusion proved to be most effective in attenuating and eliminating each of these deleterious side effects. In contrast, calcium chloride did not significantly increase heart rate or blood pressure or reverse atrioventricular block. In two instances calcium chloride produced further depression of atrioventricular conduction, leading to severe bradycardia and sinus arrest. Although calcium chloride increased left ventricular contractile force (LV dP/ dt) and cardiac index (CI), mean arterial pressure was not affected and SVR was further decreased. This study indicates that calcium chloride should not be given to reverse the side effects of diltiazem in the presence of atrioventricular conduction block or profound hypotension. Calcium chloride is indicated only when isolated myocardial depression is present and after the calcium channels have been reopened by epinephrine.
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PMID:Reversal of the adverse cardiovascular effects of intravenous diltiazem in anesthetized dogs. 1717 30