Figure 2

24-h changes in median eminence and adenohypophysial DA concentration in 11 days old male rabbit pups. Groups of 6–7 pups were killed by decapitation at 6 different time intervals throughout a 24 h cycle. Bar indicates scotophase duration. Results are the means ± SEM. Circulating prolactin levels are shown in shaded line. Letters indicate the existence of significant differences between time points within each tissue after a Tukey-Kramer's multiple comparisons test, as follows: ^a p < 0.01 vs. all time points. ^b p < 0.01 vs. 05:00 h, 09:00 h and 21:00 h. ^c p < 0.01 vs. 05:00 and 21:00 h. For further statistical analysis, see text.