Use of a Catheter-Based System to Measure Blood Flow in Hemodialysis Grafts during Angioplasty Procedures

Radioactive microspheres were used to measure blood flow in the cat stomach during exposure to saline, 0.075 M HCl, and then 15 and 30 min after exposure to 20 or 40 mM aspirin in HCl. At the end of the experiment, the stomach wall was divided into ulcerated regions and adjacent nonulcerated areas. When exposed to saline, both regions had similar blood flow: 27 +/- 5 and 25 +/- 5 ml.min-1.100 g-1 (means +/- SE). Addition of acid caused a significant increase in blood flow to 41 +/- 7 ml.min-1.100 g-1 only at those sites that eventually ulcerated in the presence of aspirin. In the adjacent nonulcerated regions, blood flow was 31 +/- 5 ml.min-1.100 g-1 and was not significantly greater than the flow recorded during saline exposure. Aspirin caused ulcer site blood flow to increase dramatically to 89 +/- 12 and 122 +/- 18 ml.min-1.100 g-1 after 15 and 30 min, whereas the adjacent nonulcerated tissue rose to 40 +/- 6 and 44 +/- 5 ml.min-1.100 g-1, respectively. The ulcer site hyperemia with acid alone suggests higher mucosal permeability in these regions allowing back-diffusion of acid and injurious agents. The present data obtained in the cat do not support the notion that ischemia plays a role in initiating nonsteroidal anti-inflammatory drug (NSAID)-induced ulcers, but rather that acute NSAID ulcers are associated initially with a hyperemia.

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Effects of vasoactive stimuli on blood flow to choroid plexus

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.1988.254.2.h286 ◽

1988 ◽

Vol 254 (2) ◽

pp. H286-H291 ◽

Cited By ~ 2

Author(s):

F. M. Faraci ◽

W. G. Mayhan ◽

J. K. Williams ◽

D. D. Heistad

Keyword(s):

Blood Flow ◽

Choroid Plexus ◽

Simultaneous Injection ◽

Measure Blood Flow ◽

Arteriovenous Shunts ◽

Anesthetized Dogs ◽

Microsphere Method ◽

Pass Through ◽

Increased Blood Flow

The goal of this study was to examine effects of vasoactive stimuli on blood flow to choroid plexus. We used microspheres to measure blood flow to choroid plexus and cerebrum in anesthetized dogs and rabbits. A critical assumption of the microsphere method is that microspheres do not pass through arteriovenous shunts. Blood flow values obtained with simultaneous injection of 15- and 50-micron microspheres were similar, which suggests that shunting of 15-micron microspheres was minimal. Blood flow to choroid plexus under control conditions was 287 +/- 26 (means +/- SE) ml.min-1.100 g-1 in dogs and 385 +/- 73 ml.min-1.100 g-1 in rabbits. Consecutive measurements under control conditions indicated that values for blood flow are reproducible. Adenosine (5 microM.kg-1. min-1 iv) did not alter blood flow to cerebrum but increased blood flow to choroid plexus two- to threefold in dogs and rabbits. Norepinephrine (0.5 micrograms.kg-1.min-1) and phenylephrine (25 micrograms.kg-1.min-1) did not affect blood flow to cerebrum but decreased blood flow to choroid plexus by approximately 50%. We suggest that 1) the microsphere method provides reproducible valid measurements of blood flow to the choroid plexus in dogs and rabbits and 2) vasoactive stimuli may have profoundly different effects on blood flow to choroid plexus and cerebrum.

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Understanding the Mind by Measuring the Brain: Lessons From Measuring Behavior (Commentary on Vul et al., 2009)

Perspectives on Psychological Science ◽

10.1111/j.1745-6924.2009.01131.x ◽

2009 ◽

Vol 4 (3) ◽

pp. 314-318 ◽

Cited By ~ 7

Author(s):

Lisa Feldman Barrett

Keyword(s):

Blood Flow ◽

Verbal Behavior ◽

History Of Psychology ◽

Physiological Changes ◽

Measure Blood Flow ◽

History Of ◽

The Mind ◽

The Brain

Throughout the history of psychology, the path of transforming the physical (muscle movements, verbal behavior, or physiological changes) into the mental has been fraught with difficulty. Over the decades, psychologists have risen to the challenge and learned a few things about how to infer the mental from measuringthe physical. The Vul, Harris, Winkielman, and Pashler article (2009) , (this issue) points out that some ofthese lessons could be helpful to those of us who measure blood flow in the brain in a quest to understand the mind. Three lessons from psychometrics are discussed.

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