The serotonin reuptake transporter (5HTT) is thought to be the principal regulator of serotonergic activity and epigenetic effects at this locus are thought to be important moderators of vulnerability to neuropsychiatric illness. In attempt to understand the basis of this regulation, several gene polymorphisms that affect 5HTT mRNA levels have been described. But to date, no clear mechanism lin...

Numerous endogenous vasoactive agents have been shown to cause lymphatic smooth muscle contraction. In this study, we assessed the ability of serotonin (5-HT) to alter lymphatic smooth muscle activity and elucidated the receptor mechanisms of 5-HT's actions. Both intralymphatic and intra-arterial administration of 5-HT significantly increased lymphatic smooth muscle activity in lymphatics perfu...

AIMS 5-Hydroxytryptamine (5-HT) is a potent vasoconstrictor and mitogen in the pulmonary vascular bed which exhibits phenotypical and functional heterogeneity according to size of the vessels. METHODS We thus investigated both contractile response and smooth muscle cell (SMC) proliferation in response to 5-HT in rat main extrapulmonary artery (MPA) and intrapulmonary arteries of the first and...

Peripheral neural 5-hydroxytryptamine (5-HT) receptors are different from both classes 5-HT1 and 5-HT2, which have been described from studies of 5-HT receptors in the brain. Recently, it has been shown that, as in the CNS, there is more than a single type of neural receptor for 5-HT in the enteric nervous system. One of these, called 5-HT1P, has a high affinity for 3H-5-HT, initiates a long-la...

BACKGROUND The 5-HT1 agonist sumatriptan, used in the treatment of migraine, can cause chest pain. AIM To investigate the effect of a therapeutic dose of sumatriptan (6 mg s.c.) on oesophageal motility. METHODS In 16 normal healthy subjects aged 19-32 years (9 males), the manometric response of the lower oesophageal sphincter (sleeve sensor), oesophageal body (four sites), stomach and phary...

Serotonin, (5-hydroxytryptamine, 5-HT, enteramine) is widely distributed in animal tissues and has been shown to have marked pharmacologic effects upon the gastrointestinal tract and cardiovascular system (1-4). Indirect evidence suggests that serotonin may play an important role in cerebral function, but, as yet, no direct connection has been established between serotonin and cerebral disease ...

Stomata are small adjustable pores formed by pairs of guard cells that enable gas exchange between leaves and the atmosphere, thus directly affecting water loss and CO2 uptake in plants. The current work focuses on the regulation of stomatal movements by red light, carbon dioxide and the circadian system and attempts to uncover molecular mechanisms that control guard cell function. The signalin...

Six plant sources of hydrolyzable tannins (HT) or HT and condensed tannins (CT; designated as HT1, HT2, HT3, HT + CT1, HT + CT2, and HT + CT3) were evaluated to determine their effects in vitro on CH(4) production and on ruminal archaeal and protozoa populations, and to assess potential differences in biological activities between sources containing HT only or HT and CT. Samples HT1, HT2, and H...