Cardiac alpha1-adrenoceptors mediate positive inotropy via myofibrillar sensitization

Article Abstract:

Alpha1-adrenoceptor agonists have advantages over standard cardiac inotropic agents because these sensitize myofibrils via a receptor-mediated mechanism. Alpha1-adrenoceptor stimulation enhances myocardial contraction without producing adverse rhythmic effects and calcium overload by increasing sensitiviity to calcium influx. This may be due to alkalinization of the intracellular pH and consequent increase in alkaline phosphatase-sensitive phosphorylation. The focus of cardiac pharmacology now centers on the phosphoinositol and adrenergic pathways in muscular contraction.

Calcium channels, Sympathomimetic agents, Adrenergic mechanisms

---

Is the relaxin system a target for drug development? Cardiac effects of relaxin

Article Abstract:

An analysis of the impact of human relaxin gene 2 product on specific receptors in the isolated atria was reviewed. Earlier research concluded that relaxin exhibited influence in the elevation of cardiac output during pregnancy while indicating the potential of the relaxin system for inotropic agent development. However, it is shown that relaxin may not possibly affect cardiac output elevation through a positive inotropic effect on the ventricular myocardium.

Drug therapy, Heart diseases

---

Kakouris et al. reply: inotropic and chronotropic effects of relaxin in vitro

Article Abstract:

An analysis of the functions of relaxin is presented. The analysis shows that relaxin functions are not limited to the inhibition of spontaneous contractions of the myometrium, cervix softening and interpubic ligament lengthening prior to parturition. It is also shown that functional correlates may be established for relaxin in high-affinity binding sites as indicated by rat heart studies.

Similar abstracts:

• Abstracts: Pharmacological prospects for alpha2-adrenoceptor antagonist therapy. Application of in situ microdialysis to measure metabolic and vascular responses in adipose tissue
• Abstracts: Structure and pharmacology of the proton-ATPases. Thiopurine biology and pharmacology
• Abstracts: Glutamate receptors and asthmatic airway disease. Subunit structure of native GABAA receptors in the mammalian CNS
• Abstracts: Is the R and R* dichotomy real? Receptor targets in William Tell country: insights into receptor biology using fluorescent proteins
• Abstracts: A physiological role for PAF in the stimulation of mammalian embryonic development

This website is not affiliated with document authors or copyright owners. This page is provided for informational purposes only. Unintentional errors are possible.