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## Re: P22 From: Lars Kunz and Günther Stark (gunther.stark@uni-konstanz.de) Date: 11/25/97 Time: 3:16:13 PM Remote Name: 134.34.3.27 ### Comments Thank you for your interesting questions, which we would like to answer as follows: 1)The time course of inactivation of the three kinds of ion channels investigated was found to be roughly identical within the comparatively large variation of the time constant found for each channel type (a factor of 5 for maxi-KCa). There was a rather close correlation between the time constant of channel inactivation and the delay in the increase of the leak conductance, i.e. a slow channel inactivation corresponded to a long delay period. All these results agree with the assumption of lipid peroxidation as the common cause of the phenomena reported. 2)We think that an increase of the leak conductance is observed only after accumulation of a minimum amount of products of lipid peroxidation. A delay in the conductance increase was also observed for planar lipid membranes in the presence of hematoporphyrin (Mirsky et al. 1991, J. Photochem.Photobiol. B 8, 315-324; Stozhkova et al. 1994, Biol. Mem. 7, 41-46). Back to the list of comments