Glycine--an important neurotransmitter and cytoprotective agent.

BACKGROUND: Glycine, the simplest of the amino acids, is an essential component of important biological molecules, a key substance in many metabolic reactions, the major inhibitory neurotransmitter in the spinal cord and brain stem, and an anti-inflammatory, cytoprotective, and immune modulating substance. MATERIAL AND METHODS: Based on available literature, we discuss some of the important biological properties of glycine. In addition, we describe some clinical disorders where glycine plays a central role, either as an essential structural element, or through its metabolism or receptors. RESULTS: The past few years have witnessed a broadening of glycine research. The traditional prime interest in aspects related to its role as an inhibitory neurotransmitter in the central nervous system has been expanded to equally emphasize other organs and tissues. With the demonstration of glycine-gated chloride channels on neurons in the central nervous system, on most leukocytes, and subsequently on other cells as well, a unifying mechanism of action accounting for many of the widespread effects of glycine has been found. CONCLUSIONS: Glycine is a simple, easily available, and inexpensive substance with few and innocuous side-effects. The diversity of biological activities is well documented in the literature. Despite this, glycine has only gained a modest place in clinical medicine.

Postoperative pain relief with high-dose epidural buprenorphine: a double-blind study.

Forty-five patients scheduled for major abdominal or intrathoracic surgery were assigned at random to two different groups. One group received 0.3 mg and the other 0.9 mg of buprenorphine epidurally to abolish postoperative pain. The first dose was given immediately upon arrival in the ICU, irrespective of pain. Subsequent medication was given on demand. The duration of action and side-effects were recorded. Both doses produced excellent and long-lasting pain relief, but no statistically significant difference was found between the groups, with regard to either the duration of action or the occurrence of side-effects.