PMID: 36185Jan 1, 1979

Presynaptic muscarinic and alpha-adrenergic receptor blocking effect of atropine on the noradrenergic neurones of the rabbit pulmonary artery

Blood Vessels
O A Nedergaard, J Schrold


The effect of atropine on the electrical-field stimulation-evoked overflow of tritium from isolated rabbit pulmonary arteries preincubated with 3H-noradrenaline was studied. Atropine (10(-4) M) and phentolamine (10(-6) M) increased stimulation-induced overfoow of tritium. Clonidine (10(-6) to 10(-5) M) and acetylcholine (10(-6) M) diminished the stimulation-evoked overflow of tritium. After the overflow had been raised by either atropine (10(-4) M) or phentolamine (10(-6) M), clonidine (10(-6) M) decreased the overflow below control values. Clonidine (10(-5) M) prevented the enhancement of tritium overflow evoked by atropine (10(-4) M). A lower concentration of clonidine (10(-6) M) only caused a partial prevention. Enhancement of the overflow by phentolamine (10(-6) and 3 X 10(-5) M) was not altered by atropine (10(-4) M). Atropine (10(-7) M), in a concentration which was without any effect on the stimulation-induced tritium overflow, prevented the reduction evoked by acetylcholine (10(-6) M). It is concluded that atropine in a low concentration blocks presynaptic inhibitory muscarinic receptors; at higher concentrations it blocks in addition presynaptic alpha-adrenoceptors.

Related Concepts

Norepinephrine, (+, -)-Isomer
Cholinergic Receptors
Adrenergic alpha-Antagonists
Pulmonary Artery Structure
Drug Interactions
Acetylcholine Sulfate (1: 1)

Trending Feeds


Coronaviruses encompass a large family of viruses that cause the common cold as well as more serious diseases, such as the ongoing outbreak of coronavirus disease 2019 (COVID-19; formally known as 2019-nCoV). Coronaviruses can spread from animals to humans; symptoms include fever, cough, shortness of breath, and breathing difficulties; in more severe cases, infection can lead to death. This feed covers recent research on COVID-19.

Chronic Fatigue Syndrome

Chronic fatigue syndrome is a disease characterized by unexplained disabling fatigue; the pathology of which is incompletely understood. Discover the latest research on chronic fatigue syndrome here.

Synapse Loss as Therapeutic Target in MS

As we age, the number of synapses present in the human brain starts to decline, but in neurodegenerative diseases this occurs at an accelerated rate. In MS, it has been shown that there is a reduction in synaptic density, which presents a potential target for treatment. Here is the latest research on synapse loss as a therapeutic target in MS.

Artificial Intelligence in Cardiac Imaging

Artificial intelligence (ai) techniques are increasingly applied to cardiovascular (cv) medicine in cardiac imaging analysis. Here is the latest research.

Position Effect Variegation

Position Effect Variagation occurs when a gene is inactivated due to its positioning near heterochromatic regions within a chromosome. Discover the latest research on Position Effect Variagation here.

Social Learning

Social learning involves learning new behaviors through observation, imitation and modeling. Follow this feed to stay up to date on the latest research.

Cell Atlas of the Human Eye

Constructing a cell atlas of the human eye will require transcriptomic and histologic analysis over the lifespan. This understanding will aid in the study of development and disease. Find the latest research pertaining to the Cell Atlas of the Human Eye here.

Single Cell Chromatin Profiling

Techniques like ATAC-seq and CUT&Tag have the potential to allow single cell profiling of chromatin accessibility, histones, and TFs. This will provide novel insight into cellular heterogeneity and cell states. Discover the latest research on single cell chromatin profiling here.

Genetic Screens in iPSC-derived Brain Cells

Genetic screening is a critical tool that can be employed to define and understand gene function and interaction. This feed focuses on genetic screens conducted using induced pluripotent stem cell (iPSC)-derived brain cells.