Author/Editor		Mohar, Urša
Title		Primerjava primernosti različnih metod za določanje učinkovitosti in narave antagonistov receptorjev H2 na dveh izoliranih organih z različnimi lastnostmi
Type		monografija
Place		Ljubljana
Publisher		Univerza v Ljubljani, Medicinska fakulteta
Publication year		2005
Volume		str. 123
Language		slo
Abstract		To determine the properties of the antagonist, which give us more information about its potency and behaviour, the method of determination of pA2 by Schild is most frequently used. In investigating the antagonist-receptor relationship, this method still proves the most precise one. As experimental models in our work with the antagonists of H2 receptors we used preparations of two isolated organs from guinea pig, the right atriumand stomach. The isolated stomach preparation has different kinetic properties from the atrium and the physiological responsiveness of this secretory organ is different from the atrium as well. In previous experiments the preparation of the isolated stomach already showed differences in comparison to the isolated atrium in the analysis of antagonist properties with the Schild method. Therefore, we wanted to examine whether determination with another method pointed to the same differences in these two isolated organs. Consequently, we used the Calderone method, which has been described as the method for the determination of antagonists' properties. This method has not yet been used with the isolated stomach preparation in order to observe the secretory response. "fhe Schild method, on the other'zand, served us to draw cotnparisons. The use of the Calderone method and the H2 receptor antagonst with insurmountable nature in high concentrations famotidine, demonstrated the slope of the regression line which was not significantly different from unity in the isolated stomach. When famotidine was used, the values of the parameter pA2 were insignificantly different in the stomach and atrium and also between the two methods. The antagonist tiotidine was further chosen for our work because, in high concentrations, it is also an insurmountable antagonist. The variability of the results in the isolated stomach was too large, so we could not make any conclusions about the statistical significance of the pA2 value. (Abstract truncated at 2000 characters).
Descriptors		HEART ATRIUM STOMACH HISTAMINE H2 ANTAGONISTS FAMOTIDINE NIZATIDINE GUINEA PIGS