Central Interleukin-1β Suppresses the Nocturnal Secretion of Melatonin

Figure 5

The effects of icv. injection of interleukin- (IL-) 1β (50 μg/animal) or Ringer’s solution (50 μL) on the relative gene and protein expression (mean ± SEM; animals per group) of enzymes of the melatonin biosynthetic pathway (tryptophan hydroxylase 1 (TPH1, (a)); aromatic-L-amino-acid decarboxylase encoded by the dopa decarboxylase (DDC, (b)); arylalkylamine-N-acetyltransferase (AANAT, (c)); hydroxyindole-O-methyltransferase (HIOMT, (d))) in ewes during the short night (SN, May/June) and long night (LN, November/December) photoperiods. All gene expression data presented in the figure were normalised to the average relative level of HIOMT gene expression in the control ewes from the SN photoperiod, which was set to 1.0. Protein expression data presented in a particular panel were normalised to the average relative level of protein expression in the control ewes from the SN photoperiod, which was set to 1.0. Different capital letters indicate significant () differences according to a two-way ANOVA followed by Tukey’s post hoc test.

(a)

(b)

(c)

(d)