PubMed Health⌕ Search

Biomedical subjects

Robert Kloner

Publications and source records attributed to Robert Kloner.

5 recordsLinked to original sources

The effect of tadalafil on the time to exercise-induced myocardial ischaemia in subjects with coronary artery disease.

OBJECTIVE: To investigate the effect of tadalafil on the time to exercise-induced myocardial ischaemia in subjects with coronary artery disease (CAD). Background CAD and erectile dysfunction (ED) share similar risk factors. It is important to know the cardiovascular effects of tadalafil in patients with CAD during physical exertion that is comparable with sexual activity. METHODS: A randomized, placebo-controlled, double-blind, two-period, crossover study comparing the effects of tadalafil 10 mg and placebo on the time to exercise treadmill test (ETT)-induced myocardial ischaemia in subjects with stable CAD (n = 23; age range: 53-75 years, all exhibited ST-segment depression >1.5 mm at screening ETT at > 5METS). Haemodynamic responses to sublingual nitroglycerin (NTG) were assessed before and after ETT. RESULTS: Compared with placebo, tadalafil did not significantly affect the time to ETT-induced ischaemia (13 min/31 s vs. 13 min/36 s, respectively). Before exercise, NTG evoked decreases in sitting systolic blood pressure (SBP) that were significantly greater when subjects received tadalafil compared with placebo, and after exercise, more subjects experienced a decrease in SBP <85 mmHg in response to NTG after taking tadalafil vs. placebo. When subjects received tadalafil compared with placebo, SBP was lower at rest (-7 mmHg; -12,-2), during ETT (-10 mmHg; -16, -3), and after ETT (-13 mmHg; -19, -7). CONCLUSION: Tadalafil did not significantly alter the time to ETT-induced ischaemia compared with placebo in subjects with CAD. Tadalafil reduced resting and exercise SBP. Due to the potential for hypotension, the concomitant use of nitrates and tadalafil is contraindicated.

Aged↗

New cellular and molecular approaches for the treatment of cardiac disease.

Similar to the kidney in uremia, end-stage cardiac failure is an outcome common to many disparate disease processes including hypertension, various inflammatory pathologies, as well as ischemic loss of tissue. In regard to the heart, cellular and molecular mechanisms responsible for heart failure have been investigated with renewed intensity over the past several years with newer techniques of molecular genetics, genomic analysis, and cell biology. Although this article reviews some recent advances made in our understanding of molecular and cellular events in the heart leading to heart failure and explores possible new targets for therapeutics, the main point is to stress the importance of investigative interactions between organ physiologists and molecular and cellular biologists. These interactions between organ physiologists and molecular geneticists is stressed and supported as a mechanism for rapid advancement for both understanding the underlying pathophysiology of human disease and the development of therapeutic strategies.

Biomedical Research↗

Pharmacotherapy for erectile dysfunction.

INTRODUCTION: Advances in understanding of the biochemistry and physiology of penile erection have led to breakthroughs in pharmacotherapy of erectile dysfunction. AIM: To provide recommendations/guidelines concerning state-of-the-art knowledge for the putative molecular and cellular mechanisms of action of centrally and peripherally acting drugs currently utilized in pharmacotherapy of erectile dysfunction. METHODS: An international consultation in collaboration with the major urology and sexual medicine associations assembled over 200 multidisciplinary experts from 60 countries into 17 committees. Committee members established specific objectives and scopes for various male and female sexual medicine topics. The recommendations concerning state-of-the-art knowledge in the respective sexual medicine topic represent the opinion of experts from five continents developed in a process over a two-year period. Concerning the Pharmacotherapy for Erectile Dysfunction Committee there were 25 experts from 10 countries. MAIN OUTCOME MEASURE: Expert opinion was based on grading of evidence-based medical literature, widespread internal committee discussion, public presentation and debate. RESULTS: Selective and potent oral PDE5 inhibitors have significantly more affinity than cGMP and form broader molecular interactions with multiple amino acids, thereby blocking access to cGMP in the catalytic sites of the PDE5 enzyme. PDE5 inhibitors, which vary as to biochemical potency, selectivity and pharmacokinetics, lead to cGMP elevation and relaxation facilitation of penile corpus cavernosum smooth muscle cells following sexual stimulation. Various centrally acting drugs influence sexual behaviour. In particular, the dopaminergic substance apomorphine is a central enhancer that acts in the paraventricular nucleus of the hypothalamus as a dopamine (D2) receptor agonist, induces and increases penile erection responses via disinhibition, following sexual stimulation. CONCLUSIONS: There is a need for more research in the pharmacotherapeutic development of central and peripheral agents for safe and effective erectile dysfunction treatment.

Apomorphine↗

Health care clinicians in sexual health medicine: focus on erectile dysfunction.

A consensus guidelines model was developed for managing erectile dysfunction (ED) by urology nurses and other health care clinicians. The model emphasizes identification of ED in all males older than 40, education and counseling as keys to intervention, and inclusion of partners whenever possible. These guidelines are intended to provide a comprehensive care model for ED patients and their partners, which would be optimally cost effective and clinically relevant. If successful, this new model will allow quality sexual health care to be provided to increasing numbers of patients and their partners.

Counseling↗