Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
Each point is the mean (± s.e.m.) expressed as a percentage of the control response obtained in the presence of 5 mm ATP using the protocol shown in Fig. 2A. The number of preparations is indicated in parentheses.
