Prospects for Creation of Cardioprotective and Antiarrhythmic Drugs Based on Opioid Receptor Agonists

It has now been demonstrated that the μ, δ(1), δ(2), and κ(1) opioid receptor (OR) agonists represent the most promising group of opioids for the creation of drugs enhancing cardiac tolerance to the detrimental effects of ischemia/reperfusion (I/R). Opioids are able to prevent necrosis and apoptosis of cardiomyocytes during I/R and improve cardiac contractility in the reperfusion period. The OR agonists exert an infarct‐reducing effect with prophylactic administration and prevent reperfusion‐induced cardiomyocyte death when ischemic injury of heart has already occurred; that is, opioids can mimic preconditioning and postconditioning phenomena. Furthermore, opioids are also effective in preventing ischemia‐induced arrhythmias

Cryptic Female Choice in Crustaceans

Cryptic female choice may be common among crustaceans , but few studies have thoroughly examined it in this diverse taxonomic group. Herein, we summarize current genetic evidence for multiple paternity and skewed offspring ratios in crustaceans, and document observations that could suggest cryptic female choice. Behaviors indicative of cryptic female choice have been reported from numerous crustacean taxa (e.g., crayfish , hermit crabs , isopods ), showcasing a diverse array of behavioral mechanisms such as failed copulations, spermatophore removal , selective sperm passage, chemical signaling , adjusting duration of receptivity, delayed copulation , or discriminative reproductive investment in favor of preferred males. We highlight a few case studies, in which a suite of different cryptic behaviors permits females to maintain control over fertilizations. The possibility of selective sperm–egg interactions is briefly discussed, and parallels to other aquatic invertebrates are drawn revealing similar cryptic choice mechanisms. The disparity of body forms and reproductive strategies found in crustaceans and the fact that they inhabit many different habitats with variable selective environments makes them an ideal model taxon for future studies on cryptic female choice