SLC1A3 and diabetes mellitus: In the second trial, the proportion of patients with diabetes, a cohort reported to have a blunted effect of glutamate, had doubled to 47%.21,22,23,24 The mechanism appears to be related to downregulation of mitochondrial glutamate transporter EAAT1 (excitatory amino acid transporter 1) in the heart of humans and animals with diabetes.23,24