Related Experiment Video

Updated: Feb 6, 2026

Murine Isolated Heart Model of Myocardial Stunning Associated with Cardioplegic Arrest
08:30

Murine Isolated Heart Model of Myocardial Stunning Associated with Cardioplegic Arrest

Published on: August 6, 2015

12.2K

Impaired coronary contraction to phenylephrine after cardioplegic arrest in diabetic patients

Nicholas Sellke1, Caroline Gordon1, Isabella Lawandy1

  • 1Division of Cardiothoracic Surgery, Cardiovascular Research Center, Rhode Island Hospital, Alpert Medical School of Brown University, Providence, Rhode Island.

The Journal of Surgical Research
|August 14, 2018
PubMed

Insights

Diabetes impairs coronary arteriolar response to phenylephrine after cardiopulmonary bypass (CP/CPB). This effect is more pronounced in diabetic patients, potentially contributing to microcirculatory dysfunction.

Area of Science:

  • Cardiovascular Physiology
  • Vascular Biology
  • Diabetic Complications

Background:

  • Cardiopulmonary bypass (CP/CPB) with cardioplegic arrest affects coronary arteriolar response in non-diabetic patients.
  • The impact of diabetes on coronary arteriolar response to alpha-1 adrenergic agonists during CP/CPB remains unclear.

Purpose of the Study:

  • To investigate the effect of diabetes on coronary arteriolar response to phenylephrine during cardiac surgery with CP/CPB.
  • To compare the microvascular reactivity between diabetic and non-diabetic patients post-CP/CPB.

Main Methods:

  • Harvested coronary arterioles (90-150 μm) from diabetic (DM) and non-diabetic (ND) patients pre- and post-CP/CPB.
  • Assessed in-vitro microvascular reactivity to phenylephrine.
  • Measured alpha-1 adrenergic receptor expression in atrial myocardium via Western blotting and immunohistochemistry.

Main Results:

  • Phenylephrine induced dose-dependent contractions in both groups pre- and post-CP/CPB.
  • Post-CP/CPB contractile response was diminished in both ND and DM groups compared to pre-CP/CPB.
  • The diminished contractile response to phenylephrine was significantly more pronounced in diabetic patients compared to non-diabetic patients post-CP/CPB.
  • No significant differences in alpha-1A and alpha-1B adrenergic receptor expression were found between groups or time points.

Conclusions:

  • Diabetes is associated with a reduced contractile response of coronary arterioles to phenylephrine following CP/CPB.
  • This altered vascular response in diabetic patients may contribute to early coronary microcirculation vasomotor dysfunction after CP/CPB.
Abstract

Keywords:
Alpha-adrenergic receptorsCardioplegiaCoronary microcirculationDiabetesMicrovascular reactivityPhenylephrineVasomotor tone

More Related Videos

Digital Handwriting Analysis of Characters in Chinese Patients with Mild Cognitive Impairment05:58

Digital Handwriting Analysis of Characters in Chinese Patients with Mild Cognitive Impairment

Published on: March 11, 2021

5.1K
Author Spotlight: Advancing Labor Management Through Electromyometrial Imaging for Understanding Uterine Contractions08:07

Author Spotlight: Advancing Labor Management Through Electromyometrial Imaging for Understanding Uterine Contractions

Published on: May 26, 2023

1.9K

Related Concept Videos

Muscle Contraction01:15

Muscle Contraction

 
96.3K
Muscle Contraction01:10

Muscle Contraction

In skeletal muscles, acetylcholine is released by nerve terminals at the motor endplate—the point of synaptic communication between motor neurons and muscle fibers. The binding of acetylcholine to its receptors on the sarcolemma allows entry of sodium ions into the cell and triggers an action potential in the muscle cell. Thus, electrical signals from the brain are transmitted to the muscle. Subsequently, the enzyme acetylcholinesterase breaks down acetylcholine to prevent excessive...
9.0K
Smooth Muscle Contraction01:25

Smooth Muscle Contraction

Smooth muscle contraction is a complex process vital for various bodily functions, from maintaining blood vessel tension to facilitating the movement of food through the digestive tract. Unlike striated muscles, smooth muscle contraction begins more slowly and lasts longer.
The onset of contraction is triggered by an increase in calcium ions within the sarcoplasm, similar to the process in striated muscle. However, smooth muscles have a relatively smaller reservoir of the sarcoplasmic...
7.8K
Pathophysiology of Diabetes01:20

Pathophysiology of Diabetes

Diabetes mellitus is a chronic metabolic disorder characterized by hyperglycemia. The four categories of diabetes are type 1 diabetes, type 2 diabetes, other specific types of diabetes, and gestational diabetes.
Type 1 diabetes is characterized by autoimmune-mediated destruction of pancreatic β cells, with environmental factors potentially triggering this process in genetically susceptible individuals. Despite many not having a family history, certain genes increase susceptibility,...
3.6K
Coronary Circulation01:21

Coronary Circulation

The heart, an organ critical to survival, gets nourishment not from the blood it pumps but from a separate circulation system known as coronary circulation. This is the shortest circulation in the body and is responsible for supplying the heart with the nutrients it needs to function effectively.
Coronary circulation begins at the base of the aorta, where two main arteries arise—the left and right coronary arteries. These arteries encircle the heart in the coronary sulcus and supply the...
7.3K
Energy Supply for Muscle Contraction01:25

Energy Supply for Muscle Contraction

Skeletal muscle fibers have the unique ability to switch between rest and contraction states, using different sources of ATP for energy. The contraction cycle and Ca2+ transport back into the sarcoplasmic reticulum for relaxation require significant ATP. However, the ATP reserves in muscle fibers are limited and can only sustain contractions for a few seconds. Additional ATP production becomes necessary for prolonged contractions. As a result, muscle fibers generate ATP through various sources,...
5.7K