Oxytocin biologic properties

Prompted by curiosity, Katsoyannis and du Vigneaud synthetized [80] in 1958, a peptide with the ring of oxytocin and the side chain of vasopressin. The hybrid molecule, vasotocin, had the biological properties of both parent hormones. Soon after its synthesis the peptide was detected in extracts from the pituitary glands of birds and reptiles and later in the pineal gland of mammals, including man. 

The disulphide ring as well as the tripeptide side-chain of oxytocin have a number of smaller side-chains. e.g. in positions 1, 2, 3, 4, 5 and 8 (see Rig. l). These side-chains have been much manipulated in several laboratories in order to study the influence of limited chemical variations on biological properties. Neither time nor space allow us to discuss here the huge body of detailed information collected. Those... 

In summary, deamino-1-seleno-oxytocin has been crystallized, and its biological properties have been shown to differ from those of crystalline deamino-oxytocin. 

Spider webs, animal hair and muscle, egg whites, and hemoglobin (the molecule that transports oxygen in the body to where it is needed) are all proteins. Peptides are oligomers of amino acids that play important roles in many biological processes. For example, the peptide hormone insulin controls our blood sugar levels, bradykinin controls our blood pressure, and oxytocin regulates uterine contraction and lactation. Thus, proteins, peptides, and amino acids are essential to the structure, function, and reproduction of living matter. In this chapter, we will first discuss the structure and properties of amino acids, then the properties of peptides, and finally the structures of proteins. 

The subject 0xytocin - molecular aspects can be treated from various points of view. One of the possible approaches is the following To-day we have quantitative data on a nximber of well-defined pharmacological properties for more than 200 synthetic peptides of the nexirohypophysial type, which can all be considered to be derivatives of oxytocin. Therefore, it is tempting to try to discover, on the basis of the pharmacological properties of these derivatives, which parts of the oxytocin molecule are essential for the characteristic biological effects of this hormone. 

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