Effects of alpha adrenergic stimulation on diameter change of the epicardial coronary artery were studied in in-situ canine heart. The diameter of the left circumflex coronary artery (LCX) was continuously measured by 10 MHz PZT crystals applied to the external wall of the LCX. Aortic pressure was measured using high fidelity catheter-tip manometer. Enhanced activity of alpha adrenergic receptor by humoral and/or somatic nerve stimulations caused a reduction of the LCX diameter despite of the systemic pressure rise.

Animals↗

PubMedDate not supplied

Magnetic resonance imaging for early detection of Takayasu arteritis.

The patient was a 15-year-old girl with suspected Takayasu arteritis. Magnetic resonance (MR) imaging, using the fast low angle shot (FLASH) technique, revealed aneurysmal dilation of the aortic root and irregular thickening of the aortic wall. Three-dimensional (3-D) contrast-enhanced MR angiography successfully demonstrated narrowing of the left carotid and left subclavian arteries. In addition, 2-dimensional (2-D) FLASH MR imaging clearly visualized narrowing of two right renal arteries and the left renal artery. These were angiographically evident. Thus, MR imaging is particularly useful for early detection of subtle arteritic changes and involvement of stenotic lesions in branch vessels in the early phase of Takayasu arteritis.

Adolescent↗

PubMedDate not supplied

Platelet aggregation during menstrual cycle and pregnancy.

Explore the source record for details and available documents.

Adenosine Diphosphate↗

PubMedDate not supplied

A case of retroperitoneal extramedullary plasmacytoma with multiple metastases.

We investigated a patient with extramedullary plasmacytoma in the retroperitoneal space with multiple metastases using abdominal CT scan and 67Ga scintigraphy. Abdominal enhanced CT revealed the retroperitoneal tumor mimicking lymphoma. 67Ga scintigraphy showed multiple tumor localization. We could detect retroperitoneal extramedullary plasmacytoma with multiple metastases using 67Ga scintigraphy. This retroperitoneal tumor may appear similar to lymphoma on CT.

Diagnosis, Differential↗

PubMedDate not supplied

Angiographic evaluation of the coronary vasodilating effect of trapidil in anesthetized closed-chest dogs.

We studied the effect of trapidil on coronary diameters of anesthetized closed-chest dogs using coronary angiography. Trapidil 2 mg/kg i.v. significantly (p less than 0.01) increased the diameter of the proximal (1.96 +/- 0.08 mm), middle (1.29 +/- 0.05 mm), and distal (0.86 +/- 0.03 mm) coronary arteries by 4.2 +/- 1.0, 7.6 +/- 1.2, and 10.8 +/- 2.2%, respectively. Nitroglycerin 20 micrograms/kg i.v. significantly (p less than 0.01) increased the diameter of classes I, II, and III arteries by 4.0 +/- 0.7, 7.7 +/- 1.3, and 7.5 +/- 1.8%, respectively. Ergonovine (0.4 mg i.v.; n = 13) reduced (p less than 0.01) the diameter of all three classes of coronary arteries by 8.2 +/- 1.2, 9.0 +/- 1.0, and 13.3 +/- 1.9%. After pretreatment with ergonovine, trapidil (n = 8) relaxed the coronary arteries from -10.4 +/- 1.7 to -2.4 +/- 1.7% constriction (p less than 0.05). These results indicate that in dogs trapidil dilates coronary arteries in a fashion similar to nitroglycerin and reverses ergonovine-induced coronary vasoconstriction.

Animals↗

PubMedDate not supplied

Effects of trapidil on forearm veins and arteries in man.

To understand the mechanisms of antianginal effects of trapidil, we examined the effects of trapidil, 100 mg i.v., on forearm veins and arteries in nine young healthy volunteers and compared the results with those of nitroglycerin, 0.3 mg s.1. At the doses used in the study, which are those in clinical use, trapidil and nitroglycerin increased forearm venous distensibility (p less than 0.05 for both) and decreased central venous pressure (CVP; p less than 0.01 for both). These results suggest that both drugs dilate veins. Forearm vascular resistance was decreased by trapidil but not by nitroglycerin. To examine the possibility that reflex vasoconstriction triggered by the decrease in CVP counteracted the direct vasodilator effect of the drugs, we studied the relationship between CVP and forearm vascular resistance while altering CVP by lower body negative pressure. Forearm vascular resistance at a comparable level of CVP was less after than before trapidil or nitroglycerin. These results suggest that both trapidil and nitroglycerin dilate forearm arteries in humans. Thus, we conclude that at a clinical dose, trapidil, as well as nitroglycerin, dilates forearm veins and arteries in humans.

Adult↗