Histamine

When we exercise, more blood flow goes to our muscles, challenging our blood vessels. Following exercise, blood flow remains elevated and seems to be the reason for many of the positive cardiovascular benefits that occur with exercise. When the actions of histamine, a molecule primarily known for its role in allergies, are blocked, there is an attenuated blood flow response following exercise. However, this effect has never been studied in the blood vessels that supply our lungs. The purpose of this study is to examine the effects of histamines on pulmonary hemodynamics following exercise.

In This experiment, the investigators would like to design a new itch model based on the temporal summation of pruritic stimuli. The hypothesis behind this study (temporal summation) is that two overlapped applications of pruritogens will result in a higher itch sensation compared with a single application.

In This experiment, the investigators would like to test following hypotheses regarding the influence of sleep fragmentation on itch: * To investigate similarity and differences between itch and pain by comparing the effect of sleep deprivation in them. * To evaluate the inflammatory state induced by sleep fragmentation via the analysis of C-reactive protein (CRP) levels from blood samples. * To correlate the anxiety and depression scores (evaluated through questionnaires) with itch and pain sensitivity and evaluate how they are affected by sleep fragmentation.

This project aims to investigate the relationship between different dimensions of catastrophizing (rumination, magnification, and helplessness) as well as some specific personality traits related to catastrophizing tendencies like anxiety sensitivity and fear sensitivity in the modulation of itch and pain intensities in an experimental setting.

In This experiment, the investigators would like to design a new itch model based on the spatial summation of pruritic stimuli. The hypothesis behind this study (spatial summation) is that two simultaneous applications of pruritogens will result in higher itch sensation compared with a single application of pruritogen.

In This experiment, the investigators would like to test following hypotheses regarding the influence of sleep deprivation on itch: * To investigate similarity and differences between itch and pain by comparing the effect of sleep deprivation in them. * To evaluate the inflammatory state induced by sleep fragmentation via the analysis of C-reactive protein (CRP) levels from blood samples. * To correlate the anxiety and depression scores (evaluated through questionnaires) with itch and pain sensitivity and evaluate how they are affected by sleep. In This experiment, the investigators would like to test following hypotheses regarding the influence of sleep fragmentation on itch: * To investigate similarity and differences between itch and pain by comparing the effect of sleep deprivation in them. * To evaluate the inflammatory state induced by sleep fragmentation via the analysis of C-reactive protein (CRP) levels from blood samples. * To correlate the anxiety and depression scores (evaluated through questionnaires) with itch and pain sensitivity and evaluate how they are affected by sleep deprivation.

Blocking histamine H1/H2 receptors blunts chronic endurance training adaptations. The current study addresses the following research question: "What is the influence of histamine H1 signaling on training adaptations following ten weeks of resistance training in human skeletal muscle." Results from this study will yield more insights into the molecular mechanisms of adaptations to exercise training.