Commercial hydrogel product for drug delivery based on route of administration.

Hydrogels are hydrophilic, three-dimensional, cross-linked polymers that absorb significant amounts of biological fluids or water. Hydrogels possess several favorable properties, including flexibility, stimulus-responsiveness, versatility, and structural composition. They can be categorized according to their sources, synthesis route, response to stimulus, and application. Controlling the cross-link density matrix and the hydrogels' attraction to water while they're swelling makes it easy to change their porous structure, which makes them ideal for drug delivery. Hydrogel in drug delivery can be achieved by various routes involving injectable, oral, buccal, vaginal, ocular, and transdermal administration routes. The hydrogel market is expected to grow from its 2019 valuation of USD 22.1 billion to USD 31.4 billion by 2027. Commercial hydrogels are helpful for various drug delivery applications, such as transdermal patches with controlled release characteristics, stimuli-responsive hydrogels for oral administration, and localized delivery via parenteral means. Here, we are mainly focused on the commercial hydrogel products used for drug delivery based on the described route of administration.

The Impact of Morphine on Reproductive Activity in Male Rats Is Regulated by Rf-Amid-Related Peptide-3 and Substance P Adjusting Hypothalamic Kisspeptin Expression.

Obviously, opiates (e.g., morphine) are associated with the suppression and dysfunction of reproductive axis. It has been reported that substance P (SP) and RF-amid-related peptide-3 (RFRP-3) can exhibit anti-opioid effects in some regions of the nervous system. Moreover, SP and RFRP-3 are deemed as neuropeptides which exert modulatory and regulatory impacts on the function of the reproductive axis. The precise interactions of morphine with SP or RFRP-3 on the parameters of the reproductive activity, however, are not fully known. The present study was aimed to determine the impacts of the interaction of morphine either with SP or RFRP-3 on the hormonal and behavioral parameters of reproductive activity in male rats. In addition, it was aimed at determining whether the effects of these interactions rely on kisspeptin/G protein coupled receptor 54 (GPR54) pathway as the main upstream pulse generator and the mediator of the function of many inputs of gonadotropin-releasing hormone (GnRH)/luteinizing hormone (LH) system or not. Altogether, the resulted data from the sexual behavior tests, radioimmunoassay of LH/testosterone, and real-time quantitative PCR for the assessment of the expression of hypothalamic Kiss1, Gpr54, and Gnrh1 genes following concomitant administration of morphine with SP or RFRP-3 revealed that the suppressing effects of morphine on the parameters of reproductive axis activity can be affected by the administration of either RFRP-3 or SP. It is advocated that SP and RFRP-3, by the modulation of the expression of hypothalamic Kiss1, can possibly antagonize the effects of morphine on GnRH/LH system and sexual behavior.