Experiments with volume overload in SHR/Frid and WKY/Frid.

Heart rate, systolic and diastolic blood pressure, and left ventricular pressure were continuously measured in volume overload experiments with SHR and WKY rats. The index for contractility dp/dtmax was determined. The initial data and the changes during overload are tabulated and compared between the strains. Overload led to a marked increase of the end-diastolic left ventricular pressure in WKY rats. The SHR overload model reacts less to the standard drug Dopamine than the normotensive strain. It combines chronic hypertension with acute volume overload and is suitable for circulation basic research and special screening experiments with prospective new cardiovascular drugs. It is bound to a high technical and preparative expenditure.

Prenatal influence of substance P on blood pressure and stress sensitivity of spontaneously hypertensive rats.

Substance P, administered i.p. to female spontaneously hypertensive rats in the last 6 d of gestation, diminishes the age dependent increase of blood pressure especially in male offspring and the additionally stress related blood pressure increase in both sexes.