ISBN: 978-83-60043-10-3 - eurobic9

Eurobic9, 2-6 September, 2008, Wrocław, Poland
P18. The Electrochemical Studies of the Complexes of Histidine Analogues
of Vasopressin and Oxytocin
J. Brasuń a , M. Cebrat b , B. Fuglewicz a , S. Plińska a , J. Świątek-Kozłowska a
a
Department of Inorganic Chemistry, Wroclaw Medical University, Szewska 38, 50-139 Wroclaw, Poland
e-mail: stasia.plinska@wp.pl,
b
Faculty of Chemistry, Wroclaw University, F. Joliot-Curie 14, 50-363 Wroclaw, Poland
The coordination abilities of different oligopeptides with many metal ions like Cu(II), Ni(II) and Zn(II) have
been studied since many years [1, 2]. Peptide hormones like oxytocin (OXT) and vasopressin (AVP) play an
important role in a human organism. They contain disulphide bridge and are able to form stable complexes e.g.
with Cu(II) and Ni(II) [3].
The biologicaly active peptides are often used as the pharmaceuticals. Some new analogues of OXT and AVP
with higher selectivity, limited side effects and higher activity, are investigated [4].
In this work the results for some the Cu(II) and Zn(II) complexes with histidine-AVP analogue (His-Tyr-Phe-
Gln-Asn-His-Pro-Leu-Gly-NH2) and OXT analogue (Ac-His-Tyr-Ile-Gln-Asn-His-Pro-Leu-Gly-NH2) are
presented. The stability constants of investigated complexes have been determined by the analysis of the voltamperometric
results.
References:
[1]. H. Kozłowski, W. Bal, M. Dyba, T. Kowalik-Jankowska, Specific structure–stability relations in
metallopeptides, Coordination Chemistry Reviews, 184, 319–346 (1999).
[2]. I. Sovago, K. Osz, Metal ion selectivity of oligopeptides, J. Chem. Soc., Dalton Trans., 3841–3854 (2006).
[3]. H. Kozłowski, B. Radomska, G. Kupryszewski, B. Lammek, C. Livera, L. D. Petit, S. Pyburn, J. Chem.
Soc., Dalton Trans., 173 (1989).
[4]. E. Trzepałka, M. Oleszczuk, M. Maciejczyk, B. Lammek, Solution structure of conformationally restricted
vasopressin analogues, A. Biochem. Pol., 51, 33-49 (2004).
_____________________________________________________________________
137