In order to examine the effect of exogenous melatonin on selected blood indices, dairy goats were given pineal gland hormone at a dose of 0.1 mg/kg body weight. Next, one and four hours after the melatonin had been administered, blood samples were collected from the goats in the control and treated groups in order to determine the levels of glucose, total cholesterol, triacyloglycerides, free f...

OBJECTIVES Changes in the activity of beta-glucuronidase, N-acetyl-beta-glucosaminidase, cathepsin D and L, alanine aminopeptidase and lysosomal acid lipase in lysosomal fractions of the liver and kidneys of mice, which were administered 20 mg/kg b.w. of exogenous melatonin (N-acetyl-5-methoxytryptamine) for 7 and 14 days were investigated. METHODS The slices of the liver and kidney were homo...

Neuroplasticity in the vocal control system of songbirds is strongly influenced by seasonal fluctuations in circulating testosterone. These seasonally plastic telencephalic structures are implicated in the learning and production of song in songbirds. The role of the indoleamine melatonin in seasonal adaptations in birds has remained unclear. In this experiment, European starlings were castrate...

OBJECTIVES There are few reports have demonstrated the effect of a change-in-light experience on the structure and function of hippocampus. A change-in-light experience also affects the circadian pattern of melatonin secretion. This study aimed to investigate developmental effect of exogenous melatonin on synaptic plasticity of hippocampus of light deprived rats. MATERIALS AND METHODS The eff...

Previous studies from our laboratory demonstrated that melatonin inhibits nitric oxide (NO)-induced relaxation in porcine coronary arteries. The present study was designed to further characterize the mechanisms underlying this inhibitory effect of melatonin. Western immunoblot studies identified the presence of melatonin type 2 (MT(2)) receptors, but not MT(1) or MT(3) receptors, in porcine cor...

Introduction ▼ Melatonin is a hormone produced by the pineal gland, regulating the circadian rhythm in mammals [1]. Exogenous administration of melatonin improves sleep quality [2], reduces jet lag [3], and possesses analgesic [4, 5], anti-oxidative [6, 7] and anti-inflammatory effects [6]. Melatonin is traditionally administered orally, but the drug displays a poor and variable bioavailability...

One of the core symptoms of the menopausal transition is sleep disturbance. Peri-menopausal women often complain of difficulties initiating and/or maintaining sleep with frequent nocturnal and early morning awakenings. Factors that may play a role in this type of insomnia include vasomotor symptoms and changing reproductive hormone levels, circadian rhythm abnormalities, primary insomnia, mood ...