Extended Data Fig. 2 ∣. Specialized dopamine release in the MPOA during appetitive mating behaviors.

a-d, Optogenetically stimulating all dopaminergic inputs to the MPOA (in TH-Cre males, a) increased appetitive sniffing behavior (b: n = 6 males) and decreased mounting latency (c: n = 5 males). The same stimulation did not further increase the fraction of males that mount in the first 15 minutes after introduction of the female (d), as this fraction was already near ceiling in the absence of stimulation (n = 6 trials from 6 males, mean ± 95% c.i.).

e, dLight1.1 expression and fiber location in the MPOA (scale bar: 200 μm).

f, The average dLight1.1 signal remained largely flat when a male mouse approached another male (n = 7 males).

g-i, Normalizing the durations of different bouts of approach to the female to a fixed “stretched" time across bouts (g) still results in a ramp-and-drop profile in the dLight1.1 signal (h). This suggests that ramps are not the result of averaging of square-shaped signals of varying durations. For illustration purposes, we set this fixed stretched time to 10 seconds, the approximate median length of a sniffing bout. Normalizing the bout lengths of sniffs in a similar manner did not reveal any increase in dopamine release either during or after the sniffs (i) (n = 6 males). dLight1.1 signal is calculated as the difference between the signal at 465-nm excitation and the signal at the isosbestic excitation wavelength of 405 nm, after the 405-nm trace has been linearly scaled to fit the 465-nm trace. See also Fig. 2b.

j-n, Quantification of the magnitude of the ramp and of the drop in the dLight1.1 signal (j) shows greatly diminished dopamine ramps (k) and drops (l) after satiety. The differences between baseline and post-satiety magnitudes of the ramp and of the drop persisted even after we sub-selected all pairs of sniffs (one per condition) with matching latencies to sniff onset (i.e. with latencies that differed by <2 seconds; 81% of the sniffs were matched) (m,n). Latency to sniff onset was defined as the number of minutes since female entry (n = 8 baseline and 6 satiated males).

o, Overlay of changes in MPOA dLight1.1 signal and male speed surrounding each sniff.

p,q, Scatter plots of dLight1.1 signal and male speed (both in 1-s bins) in the 5-s window surrounding the sniffs in two example males (Pearson correlation; p: n = 80 trials; q = 50 trials).

r, Moment-to-moment dLight1.1 signal in the MPOA is more correlated with male speed than with male-female distance, which also depends on female movements (n = 6 males). Correlation coefficients are calculated as in p and q.

s-u, Same as o-q but for correlation between dLight1.1 signal and male-female distance (Pearson correlation; t: n = 80 trials; u = 50 trials).

Mean ± s.e.m. unless otherwise specified. ***p<0.001. See Supplementary Table 1 for statistics.