Ablation of Tph1 gene in dams decreased circulating serotonin and calcium on day 1 and 10 of lactation.

<p>Wild-type (WT) mouse dams were given saline and Tryptophan hydroxylase knock-out dams given either saline (<i>Tph1^−/−</i>) or daily injections of exogenous 5-HTP (100 mg/kg; <i>Tph1^−/−</i> (5-HTP)), from pregnancy d20 to lactation d10. (A) Serum serotonin (d1 and d10 of lactation) and (B) mammary serotonin concentrations (d10 of lactation). (C) Serum calcium concentration (d1 and d10 of lactation). All values are the mean ± SEM (n = 7). Groups with different letters are significantly different (<i>P</i><0.05).