Figure 11.
Effects of MT (10−7 m) in the absence or presence of various antagonists (10−6 m each) and an OTR agonist (10−7 m) on the conversion of tritiated pregnenolone into P and 17OH-Δ5P by frog hypothalamic explants. 4, [d(CH2)51, Tyr(Me)2, Arg8]VP, V1aR antagonist; 6, [d(CH2)51, d-Ile2, Ile4, Arg8]VP, V2R antagonist; 7, [d(CH2)51, Tyr(Me)2, Thr4, Orn8, des-Gly-NH29]VT, OTR antagonist; 8, [Thr4, Gly7]OT, OTR agonist. The values were calculated from the areas under the peaks in chromatograms similar to those presented in Figure 5. Results are expressed as percentages of the amount of each steroid formed in the absence of peptide (control). Values are the mean ± SEM of four independent experiments. ***p < 0.001 versus control; #p < 0.05, ###p < 0.001 vs MT-stimulated levels; NS, not statistically different from control; ns, not statistically different from MT-stimulated levels (one-way ANOVA followed by a post hoc Bonferroni’s test).