5-HT2A receptor is the predominant receptor mediating contraction of the isolated porcine distal ureter to 5-HT in young and old animals

Current and emerging pharmacological targets for medical expulsive therapy

The primary goals of medical expulsive therapy are to increase the rate of stone expulsion along the ureter to avoid ureteral obstruction and reduce ureteral colic and thus avoid the need for surgical and more invasive interventions. This review focussed on the findings from in vivo and in vitro animal and human studies that have investigated the pharmacological mechanisms controlling ureteral motility and their translation to current and potentially new clinically used drugs for increasing the rate of stone expulsion along the ureter. The complicated contractility profile of the ureter, which alters with age, tissue segment region, orientation and species contributes to the difficulty of interpreting studies on ureteral pharmacology, which translates to the complexity of discovering ideal drug targets for medical expulsive therapy. Nevertheless, the current drug classes clinically used for patients with stone lodgement include α₁ -adrenoceptor antagonists, calcium channel blockers and NSAIDS, whilst there are promising targets for drug development that require further clinical investigations including the phosphodiesterase type 5 enzyme, β-adrenoceptors and 5-HT receptors.

Natural Products with Analgesic Effect from Herbs and Nutraceuticals Used in Traditional Chinese Medicines

BACKGROUND

Pain is one of the most common clinical symptoms . This review aims to describe research on herbs and their active ingredients in treating pain and provide a valuable reference for the development and utilization of analgesic traditional Chinese medicine (TCM).

MATERIAL AND METHODS

The literature search was performed from 1995 to October 2016, covering the relevant studies that concern the treatment of pain with TCM. Active ingredients extracted from TCM with analgesic activity are summarized and classified into six categories, including polysaccharides, saponins, alkaloids, flavonoids, terpenoids, and other constituents.

RESULTS

There are two pathways constituting the analgesic mechanisms of TCM: through the central nervous system and the peripheral nervous system. The former pathway includes increasing the content of endogenous analgesic substances like opiate peptide, cutting down the second messenger of neurotransmitter like nitric oxide (NO), reducing the content of prostaglandin E2 (PGE2) in brain tissues, blocking the central calcium channel, reducing excitatory amino acids in brain tissues, inhibiting their receptors and raising the content of the central 5-hydroxytryptamine (5-HT). The latter one usually involves the decrease in the secretion of peripheral algogenic substances, the induction of pain-sensitive substances, the accumulation of a local algogenic substance, the increase in the release of peripheral endogenous analgesia materials and the regulation of c-Fos gene (immediate early gene).