Isolated cases of gallstone formation have been associated with use of lanreotide, particularly over long periods of time. Pharmacology
Lanreotide is a synthetic analogue of somatostatin, a naturally occurring inhibitory hormone which blocks the release of several other hormones, including growth hormone, thyroid-stimulating hormone (TSH), insulin and glucagon. Lanreotide binds to the same receptors as somatostatin, although with higher affinity to peripheral receptors, and has similar activity. However, while somatostatin is quickly broken down in the body (within minutes), lanreotide has a much longer half-life, and produces far more prolonged effects. Formulations
Lanreotide is available in two formulations: a sustained release formulation (sold under the trade name Somatuline LA), which is injected intramuscularly every ten or fourteen days, and an extended release formulation (UK trade name Somatuline Autogel, or Somatuline Depot in the US), which is administered subcutaneously once a month. Self-assembling properties
Lanreotide has been shown to spontaneously self-assemble into monodisperse nanotubes of 24.4 nm diameter and has been thereafter used as a fruitful and versatile model system in several biophysical studies. References
External links
"Lanreotide". Drug Information Portal. U.S. National Library of Medicine.
The initial in vitro studies appeared to indicate a major role for ester hydrolysis but, with accumulation of clinical data over time, the preponderance of evidence indicated that Hofmann elimination at physiological pH is the major degradation pathway vindicating the premise for the design of atracurium to undergo an organ-independent metabolism.Hofmann elimination is a temperature- and pH-dependent process, and therefore atracuriums rate of degradation in vivo is highly influenced by body pH and temperature: An increase in body pH favors the elimination process, whereas a decrease in temperature slows down the process. Otherwise, the breakdown process is unaffected by the level of plasma esterase activity, obesity, age, or by the status of renal or hepatic function. On the other hand, excretion of the metabolite, laudanosine, and, to a small extent, atracurium itself is dependent on hepatic and renal functions that tend to be less efficient in the elderly population. The pharmaceutical presentation is a mixture of all ten possible stereoisomers. Although there are four stereocentres, which could give 16 structures, there is a plane of symmetry running through the centre of the diester bridge, and so 6 meso structures (structures that can be superimposed by having the opposite configuration then 180° rotation) are formed. This reduces the number from sixteen to ten. There are three cis-cis isomers (an enantiomeric pair and a meso structure), four cis-trans isomers (two enantiomeric pairs), and three trans-trans isomers (an enantiomeric pair and a meso structure).