Vasopressin amino acid sequence

Fig. 1. Stmcture of oxytocin and arginine vasopressin. Numbers indicate approximate location of amino acids sequences found in Table 1. A, oxytocin B,...

Vasopressin/Oxytocin. Figure 1 Amino acid sequence of AVP and OT. The disulphide bridge between Cys 1 and Cys 6 is shown. 

In this work we will focus on the use of the cubic phase as a delivery system for oligopeptides - Desmopressin, Lysine Vasopressin, Somatostatin and the Renin inhibitor H214/03. The amino acid sequences of these peptides are given in Table I. The work focuses on the cubic phase as a subcutaneous or intramuscular depot for extended release of peptide drugs, and as a vehicle for peptide uptake in the Gl-tract. Several examples of how the peptide drugs interact with this lipid-water system will be given in terms of phase behaviour, peptide self-diffusion, in vitro and in vivo release kinetics, and the ability of the cubic phase to protect peptides from enzymatic degradation in vitro. Part of this work has been described elsewhere (4-6). 

Oxytocin is a 9-amino-acid peptide with an intrapeptide disulfide cross-link (Figure 37-5). Its amino acid sequence differs from that of vasopressin at positions 3 and 8. 

The amino acid sequences in (a) oxytocin and (b) vasopressin. The differing amino acids are boxed. 

The second hormone that originates from the posterior pituitary gland is antidiuretic hormone, or vasopressin. It has the following amino-acid sequence ... 

As we saw in the case of vasopressin and oxytocin (Section 9.4), small changes in amino acid sequence can cause profound differences in the functioning of proteins. For example, a minor change in sequence in the blood protein hemoglobin causes the fatal sickle-cell disease. 

Amino acid sequences of oxytocin and vasopressin. The difference in oniy two amino acids (shown in red) in these two compounds resuits in very different physioiogicai activity. The C-terminai amino acid has an amide structure (Giy-NH2) instead of -COOH. 

Figure 4.7. Amino acid sequence of vasopressin and related peptides...

All the pieces of the formulas of both oxytocin and vasopressin fell into place when, in 1953, several laboratories independently published the complete amino acid sequence of both these hormones. It thus became obvious that each of them contained a 20-member disulfide ring and tripeptide side chain. Oxytocins obtained from man, beef, hog, horse, sheep, and... 

Oxytocin and vasopressin (Fig. 24.6) are two rather small polypeptides with strikingly similar structures (where oxytocin has leucine, vasopressin has arginine, and where oxytocin has isoleucine, vasopressin has phenylalanine). In spite of the similarity of their amino acid sequences, these two polypeptides have quite different physiological effects. Oxytocin occurs only in the female of a species and stimulates uterine contractions during childbirth. Vasopressin occurs in males and females it causes contraction of peripheral blood vessels... 

H-Cys-Tyr Phe-Glu(NH2)-Asp(NH2)-Cys-Pro-Leu-Gly-NH2 Figure 4.7. Amino acid sequence of vasopressin and related peptides... 

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