PMID: 9538938Apr 16, 1998Paper

Measurement of left ventricular maximal isovolumetric pressure in rats: effects of antihypertensive drugs and diabetes mellitus

Basic Research in Cardiology
T IwaiH G Zimmer

Abstract

We developed a method for measuring left ventricular maximal isovolumetric pressure (LVMIP) in intact rats and applied it in the presence of acutely administered antihypertensive drugs and in experimental diabetes mellitus. The combination of a 2 French Fogarty arterial embolectomy balloon catheter with a new ultra-thin shaft (0.25 mm diameter) Millar ultra-miniature pressure tip catheter was used. Closed-chest, thiopental anaesthetized female Sprague-Dawley rats received the beta-adrenoceptor blocker metoprolol (1 mg/kg/h), the alpha-adrenoceptor blocker prazosin (0.1 mg/kg/h), and the calcium antagonist nifedipine (0.5 mg/kg/h). They were applied as continuous i.v. infusion for 30 minutes. The angiotensin II type 1 (AT1) receptor antagonist losartan (3 mg/kg) was applied as bolus i.v. injection. Diabetes mellitus was induced by a single tail vein injection of streptozotocin (60 mg/kg) five weeks prior to hemodynamic measurements. Under control conditions, left ventricular systolic pressure (LVSP) was 136.5 +/- 3.7 mmHg and increased to 263 +/- 5.4 mmHg when the balloon was inflated (LVMIP). LVSP was significantly lower in the presence of prazosin, metoprolol, nifedipine, and in diabetic rats. However, LVMIP was significantly ...Continue Reading

Related Concepts

Related Feeds

Adrenergic Receptors: Trafficking

Adrenergic receptor trafficking is an active physiological process where adrenergic receptors are relocated from one region of the cell to another or from one type of cell to another. Discover the latest research on adrenergic receptor trafficking here.

Antihypertensive Agents: Mechanisms of Action

Antihypertensive drugs are used to treat hypertension (high blood pressure) which aims to prevent the complications of high blood pressure, such as stroke and myocardial infarction. Discover the latest research on antihypertensive drugs and their mechanism of action here.