Contribution of Thromboxane A2 in Rat Common Carotid Artery Response to Serotonin

Serotonin is a vasoactive substance that in different blood vessels mostly induces vasoconstriction. Considering the important role of common carotid artery in brain blood supply, the aims of this study were to investigate the effect of serotonin on isolated rat common carotid artery and also to examine participation of intact endothelium, cyclooxygenase products, Ca++ channels and 5-HT2 receptors in serotonin-evoked action. Endothelium was mechanically removed from some vascular rings. Circular artery segments were placed in organ baths containing Krebs–Ringer bicarbonate solution. Cumulative concentration-contraction curves for serotonin were obtained in rings previously equilibrated at basal tone. Serotonin produced concentration-dependent contraction, which was unaltered by endothelial denudation. Serotonin-induced effect was notably and comparably reduced by indomethacin (cyclooxygenase inhibitor) or OKY–046 (thromboxane A2-synthase inhibitor) on intact or denuded rings. Nifedipine (Ca++ channel blocker) or ketanserin (5-HT2 receptor antagonist) strongly reduced serotonin-evoked effect. Our results suggest that serotonin produced concentration-dependent and endothelium-independent contraction of carotid artery, which was initiated by activation of 5-HT2 receptors located on smooth muscle cells and mediated via L-type Ca++ channels. Thromboxane A2 from smooth muscle cells notably contributed to the overall contraction of carotid artery induced by serotonin

Corticosteroids in Emergency Pathologies

Ever since their discovery in the fifties of the last century, as an anti-inflammatory drugs for the treatment of rheumatoid arthritis, corticosteroids have found a significant place and wide application in various fields of medicine. Their effects are known to be diverse. The most significant ones are the anti-inflammatory, anti-allergic, and immunosuppressive effects. Furthermore, they affect the hematopoietic system. Corticosteroids produce complex metabolic effects by stimulating glyconeogenesis, increasing the uptake of amino acids in the liver and kidneys, and enhancing lipolysis. Given that natural adrenocortical hormones are synthesized under the influence of stress, it is expected that in the emergency situations, where we face vitally endangered patients whose body is under the stress due to respiratory insufficiency or impaired hemodynamics, corticosteroids do have significant place in the treatment. Thus, these drugs are used in the treatment of acute exacerbation of chronic obstructive pulmonary disease and asthma, in anaphylactic reactions, spinal shock, Addisonian crisis, and sepsis. During the COVID-19 pandemic, corticosteroids found their place in certain stages of treatment, as well as in many national protocols for the treatment of COVID-19 patients. Hence, the use of corticosteroids in the emergency pathologies will be reviewed in this chapter

Pharmacotherapy of Gestational Diabetes Mellitus: Current Recommendations

The incidence of gestational diabetes mellitus (GDM) is still rising, and this pathological condition is strongly associated with some serious adverse pregnancy outcomes. Therefore, GDM must be timely recognized and adequately managed. Treatment of GDM is aimed to maintain normal glycemia and it should involve regular glucose monitoring, dietary modification, lifestyle changes, moderate physical activity, and pharmacotherapy, when necessary. As for the pharmacotherapy, needed in approximately one-third of GDM women, insulin administration is the first choice of pharmacological treatment, although oral hypoglycemic drugs, for example, metformin (a biguanide agent) or glyburide (a second-generation sulfonylurea drug), could be indicated, too. Metformin is considered as a reasonable and safe first-line alternative to insulin. If comparing two oral agents, metformin seems to be safer than glyburide, since glyburide was found to be linked to neonatal hypoglycemia and higher birth weight, which can for example increase the hazard for shoulder dystocia and a necessity for Cesarean delivery. Finally, it should be underlined that many pregnant women turn to complementary and alternative medicine for health maintenance or symptom relief, including traditional herbal medicine and the use of supplements. Given the previous facts, this chapter will address current pharmacotherapy options and challenges related to GDM treatment