Jan 1, 1975

On the mechanism of the relaxing adrenaline effect on cat jejunum

Acta Physiologica Et Pharmacologica Bulgarica
V Petkov, R Radomirov


The effect of propranolol, phentolamine, papaverine, theophyline and Ca++, administered in different combinations of their threshold doses, on the relaxing effect of adrenaline was studied on an isolated segment of proximal jejunum of male cats. It was established that phentolamine weakened the relaxing effect of adrenaline, while propranolol had no effect on it. Papaverine potentiated the relaxinf effects of adrenaline both when administered alone and in combination with propranolol or with phentolamine. Theophylline weakened the relaxing effect of adfrenaline and of the combination phentolamine-adrenaline. Ca++ increased the smooth-muscle tone. The interpretation of the results obtained leads to the fundamental conclusions that the relaxing effect of adrenaline on cat jejunum is more alpha- than beta-adrenergically determined and that the system of the cyclic AMP participates in its realization. At the smae time, however, the possibility of participation of other mechanisms is not excluded. The smooth-muscle effect of papaverine and theophylline is not determined only by their inhibitory effect on phosphodiesterase.

  • References
  • Citations


  • We're still populating references for this paper, please check back later.
  • References
  • Citations


  • This paper may not have been cited yet.

Mentioned in this Paper

Phosphodiesterase Inhibitors
Malignant Neoplasm of Jejunum
Phosphoric diester hydrolase
Smooth Muscle
Cyclic AMP
Adrenergic beta-Agonists
Adrenergic alpha-Agonists
Adrenergic alpha-Antagonists

About this Paper

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.

Synthetic Genetic Array Analysis

Synthetic genetic arrays allow the systematic examination of genetic interactions. Here is the latest research focusing on synthetic genetic arrays and their analyses.

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.

Head And Neck Squamous Cell Carcinoma

Squamous cell carcinomas account for >90% of all tumors in the head and neck region. Head and neck squamous cell carcinoma incidence has increased dramatically recently with little improvement in patient outcomes. Here is the latest research on this aggressive malignancy.

Signaling in Adult Neurogenesis

Neural stem cells play a critical role in the production of neuronal cells in neurogenesis is of great importance. Of interest is the role signalling mechanisms in adult neurogenesis. Discover the latest research on signalling in adult neurogenesis.

Psychiatric Chronotherapy

Psychiatric Chronotherapy considers the circadian rhythm as a major factor for optimizing therapeutic efficacy of psychiatric interventions. Discover the latest research on Psychiatric Chronotherapy here.

Epigenetic Memory

Epigenetic memory refers to the heritable genetic changes that are not explained by the DNA sequence. Find the latest research on epigenetic memory here.

Bone Marrow Neoplasms

Bone Marrow Neoplasms are cancers that occur in the bone marrow. Discover the latest research on Bone Marrow Neoplasms here.