ABSTRACT
The effect of exogenously administered vasopressin was observed on captopril induced vasodilatation in hindquarters of anaesthetised rats. Drops of perfusate were counted for 6 min and mean of the outflow was expressed as drops per min (dpm). In the control group (n = 6) the rate of flow was 9.5 +/- 1.04 dpm which increased to 12.33 +/- 1.36 dpm following captopril (200 micrograms/ml) infusion. In test group (n = 6) pretreated with vasopressin (4 I.U./kg 1 hr before) the rate of flow was 9.16 +/- 0.98 dpm which was reduced to 5.5 +/- 1.04 dpm following infusion with captopril. It is concluded that vasopressin reverses the vasodilatory effect of captopril.
Subject(s)
Animals , Captopril/pharmacology , Female , Male , Rats , Rats, Inbred Strains , Vasodilation/drug effects , Vasopressins/pharmacologyABSTRACT
Cardiac arrhythmias and cardiac arrest were induced in pentobarbitone anaesthetised cats by slow intravenous infusion of ouabain. The dose of ouabain required for the induction of the stages of arrhythmias and cardiac arrest and the maximum pressor effect induced by ouabain were assessed in control and clonidine pretreated cats. Clonidine caused significant delay in the onset of cardiotonic effects of ouabain and inhibition of the maximum pressor effect of ouabain. The inhibition of cardiotoxic and pressor effects of ouabain may be the result of clonidine's effect on the neural components of ouabain action.
Subject(s)
Animals , Arrhythmias, Cardiac/chemically induced , Blood Pressure/drug effects , Cats , Clonidine/pharmacology , Female , Heart Arrest/chemically induced , Heart Diseases/chemically induced , Hemodynamics/drug effects , Male , Ouabain/antagonists & inhibitorsABSTRACT
AChE activity was determined in the brain and heart of normal, acute totally starved, chronically semi-starved and chronically protein restricted groups of adult male rats. Neither acute total starvation nor chronic semi-starvation produced significant changes in AChE activity and protein content of the brain, while AChE activity and protein content in the heart were significantly decreased (P less than 0.01) after semi-starvation. Protein restriction, however, produced a significant decrease in AChE activity and protein content of both brain (P less than 0.01) and heart (P less than 0.001).
Subject(s)
Acetylcholinesterase/metabolism , Animals , Brain/enzymology , Male , Myocardium/enzymology , Protein Deficiency/enzymology , Proteins/metabolism , Rats , Starvation/enzymologyABSTRACT
Acetylcholine (ACh) levels and protein content in brain and heart were determined in normal, acutely starved, chronically semi-starved and chronically protein restricted groups of adult male rats. The only change observed in acute starvation and chronic semi-starvation was an increase in ACh level with a decrease in protein content in the heart, no change was observed in the brain. Protein restriction, however, produced a significant rise in ACh levels with a decrease in protein content of both brain and heart.