. "Any process that stops, prevents, or reduces the frequency, rate or extent of the regulated release of a neurotransmitter." . . . . . "conotoxin activity" . "negative regulation of neurotransmitter secretion" . "down regulation of neurotransmitter secretion" . "down-regulation of neurotransmitter secretion" . "downregulation of neurotransmitter secretion" . "inhibition of neurotransmitter secretion" . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .