Figure 4.

Adult fertility in knock-out and control groups. A, Frequency of estrous cycle stage was monitored for 28 d in GABA-specific LEPR knock-out females (gray bars; n = 9) and controls (black bars; n = 10). A significant decrease in time spent in proestrus was seen in the knock-out females. B, The time from pairing with a wild-type male to first litter in GABA knock-out females (gray bar; n = 10) was longer than in littermate controls (black bar; n = 10). Number of days between litters was significantly increased in male GABA-specific knock-out animals (n = 7 in both groups). The same trend was seen in surviving females, but low animal number limited statistical comparison (n = 3). C, Frequency of estrous cycle stage was monitored for 10 d in glutamate-specific knock-out mice (white bars; n = 9) and control littermates (black bars; n = 9). No significant differences were seen between the groups. D, Time to first litter and number of days between litters were the same for all glutamate-specific LEPR knock-out females and males (white bars; n = 6 and 9) compared with littermate controls (black bars; n = 8 and 9). *p < 0.05. ***p < 0.001.