Flow diagram for atropine study.

<p>The flow diagram is for a crossover study in humans with impaired glucose tolerance and was designed so that each subject would receive all 8 graded glucose infusions. The same peptide(s) was administered during 2 successive visits- once with saline and once with atropine. First, the order of the peptide infusions was randomized. Second, the order of saline or atropine administration was randomized for each peptide. For example, if the subject was randomized to first receive Xen alone, this person would receive Xen in study visits 1 and 2. The atropine and saline infusions would then be randomized to visit 1 and 2. Eight subjects received all 8 graded glucose infusions. One subject received 6 infusions but did not receive either infusion with Xen alone. One subject received only the 2 infusions with GIP plus Xen.