Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0015672 (fatigue)
 51,768 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

1. Intravenous infusion of the individual components of the renin-angiotensin system caused drinking in dogs in water balance. 2. Angiotensin II was the most potent and rapidly acting peptide inducing drinking. The minimum effective rate of infusion was between 8.3 and 16.6 X 10(-12) mole kg-1 min-1 which yield blood levels of angiotensin II that fell well within physiological limits for the dog and were mildly pressor. Angiotensin I and synthetic renin substrate caused less drinking than angiotensin II, and angiotensin III was the least effective dipsogen. 3. Renin caused significant drinking when infused I.V. at a rate of 0.5 u. min-1 for 15 min. Drinking was slower in onset and continued for longer than after other components of the renin-angiotensin system. 4. Within the dose range 1875-15,000 X 10(-12) mole of angiotensin II the amount of water drunk depended more on the rate of infusion than on the duration of the infusion. 5. During an I.V. infusion of angiotensin II lasting 2 hr, the rate of drinking was greatest during the first 15 min. After this declined progressively. 6. A delay of 1 hr after the start of an intravenous infusion of angiotensin II before access to water was allowed, did not significantly reduce the amount of water drunk. Nor did infusion of isotonic saline for 105 min reduce drinking in response to a subsequent infusion of angiotensin II. However, a preload of dilute milk approximately equal in volume to the amount of water normally drunk in response to I.V. angiotensin II significantly reduced drinking. Therefore the dog stopped drinking during long-term infusions of angiotensin II owing to the action of satiety mechanisms and not to tachyphylaxis or fatigue. 7. Intracarotid infusion of angiotensin II, angiotensin I, synthetic renin substrate and angiotensin III, at 40 X 10(-12) mole min-1 also caused drinking. Intakes of water were similar to the intakes after I.V. infusion at six times the arterial rate, except that angiotensin I was relatively less effective by intracarotid infusion than by I.V. infusion. 8. Renin, infused at 0.5 u. min-1 for 15 min, was much less effective by intracarotid infusion than by intravenous. 9. These results are compatible with a role for circulating angiotensin II in the thirst of hypovolaemia or moderate extracellular dehydration.
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PMID:Systemic angiotensin-induced drinking in the dog: a physiological phenomenon. 65 Apr 70

The pharmacokinetics and pharmacodynamics of the ACE inhibitor quinaprilat have been studied in six chronic haemodialysis (HD) patients and in six patients undergoing continuous ambulatory peritoneal dialysis (CAPD) after a single oral dose of 2.5 mg quinapril. Mean tmax and Cmax values (SEM) for quinaprilat in interdialytic HD patients were 4.0 (0) h and 84 (8.4) ng.ml-1 respectively, and they did not differ significantly from those in CAPD patients (4.7 (0.7) h and 64 (5.7) ng.ml-1). Elimination half lives were 30 (10.1) h (HD) and 34 (7.3) h (CAPD). Cmax, tmax, t1/2, and AUC were increased and CL was decreased compared to data reported previously after giving 2.5 mg to healthy subjects. Peritoneal clearance was calculated as 0.1 (0.1) ml.min-1, thus less than 0.5% of the dose were removed within 24 h by CAPD. ACE activity was suppressed by more than 93% between 4 and 24 h postdose (P < 0.001). It decreased in both groups with increasing plasma quinaprilat levels. Angiotensin II concentration compared to baseline was significantly decreased at 4 hours (-30.4 +/- 10%) and 24 h (-30 +/- 9.9%) (P < 0.05, n = 11), while active plasma renin concentration was still significantly increased at 48 h postdose (+ 60.2 +/- 14.5%, P < 0.01). Mean arterial pressure 24 h postdose was significantly (P < 0.05) decreased in HD (-12 mmHg) and CAPD patients (-20 mm Hg). Only two patients reported unwanted effects (fatigue, dizziness, nausea, and weakness). In conclusion, due to its long lasting effect on ACE activity and on blood pressure in terminal renal failure a starting dose of quinapril 2.5 mg o.d. may be used in hypertensive HD and CAPD patients.
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PMID:Pharmacokinetics and pharmacodynamics of quinaprilat after low dose quinapril in patients with terminal renal failure. 838 27