• reduction in gephyrin cluster density in the hippocampus at P60 and P130 but not at P40 (J:141850)

• however, clustering is unaffected in other areas of the brain (J:141850)

• a rapid decline in health is observed by the end of the fourth postnatal week and mice die within 3 days of overt signs of stress including reduced locomotion, round pupils, and reduced weight gain

• lack of locomotion is observed as health declines

• some mice exhibit overt epilepsy within several days prior to death; typical seizures start with rearing adn loss of postural control, followed by running fits and violent convulsions

• some mice exhibit overt epilepsy within several days prior to death; typical seizures start with rearing adn loss of postural control, followed by running fits and violent convulsions

• 12.6% (13 out of 103) referred to as "mini" were significantly smaller at P7 and died by 3 weeks after birth

• remaining mutant were phenotypically normal up to the forth postnatal week and their weight was statistically indistinguishable from controls

• many more neurons stain positively for activated caspase-3 in the brains of homozygous mice at 2 weeks and 8weeks after birth

• more activation of caspase-3 in the cell body layers of the hippocampus were found note: level of synGAP protein correspond to 20-25% of wild-type in ""mini"" group and 37.5% of wild-type in normal group more activation of caspase-3 in the cell body layerof the hippocampus were found note: level of synGAP protein correspond to 20-25% of wild-type in ""mini"" group and 37.5% of wild-type in normal group more activation of caspase-3 in the cell body layers of the hippocampus were found note: level of synGAProtein correspond to 20-25% of wild-type in ""mini"" group and 37.5% of wild-type in normal group more activation of caspase-3 in the cell body layers of the hippocampus were found

• level of synGAP protein correspond to 20-25% of wild-type in ""mini"" group and 37.5% of wild-type in normal group

• level of synGAP protein correlate with severity of neuronal apoptosis

• many more neurons stain positively for activated caspase-3 in the brains of homozygous mice at 2 weeks and 8weeks after birth

• more activation of caspase-3 in the cell body layers of the hippocampus were found note: level of synGAP protein correspond to 20-25% of wild-type in ""mini"" group and 37.5% of wild-type in normal group more activation of caspase-3 in the cell body layerof the hippocampus were found note: level of synGAP protein correspond to 20-25% of wild-type in ""mini"" group and 37.5% of wild-type in normal group more activation of caspase-3 in the cell body layers of the hippocampus were found note: level of synGAProtein correspond to 20-25% of wild-type in ""mini"" group and 37.5% of wild-type in normal group more activation of caspase-3 in the cell body layers of the hippocampus were found

• level of synGAP protein correspond to 20-25% of wild-type in ""mini"" group and 37.5% of wild-type in normal group

• level of synGAP protein correlate with severity of neuronal apoptosis

• in the elevated plus maze, mutants spend more than half the session time on the open arms and moved freely on them compared to wild-type mice that remain mostly on the closed arms, indicating reduced fear of height

• in the light/dark box text, mutants spent more time in the brightly illuminated space than wild-type mice, although the number of transitions between light and dark spaces did not differ

• in the open-field test, mutants spend a longer time in the central area than wild-type mice and exhibit higher levels of locomotor activity, indicating reduced fear of open spaces

• in the elevated plus maze, mutants spend more than half the session time on the open arms and moved freely on them compared to wild-type mice that remain mostly on the closed arms, indicating reduced fear of height

• in the light/dark box text, mutants spent more time in the brightly illuminated space than wild-type mice, although the number of transitions between light and dark spaces did not differ

• in the open-field test, mutants spend a longer time in the central area than wild-type mice and exhibit higher levels of locomotor activity, indicating reduced fear of open spaces

• in the open-field test, mutants exhibit higher levels of locomotor activity

• in the hole-board test, while wild-type mice explore different holes in a random or successive manner, mutants show a tendency towards making repeated head-dips into the same hole, indicating stereotyped dip behavior; occurrence of stereotypic dip was significantly greater, however the total number of head-dips did not differ from wild-type

• mutants show a tendency to perform consecutive head-dips of more than 4 repetitions, a behavior not seen in wild-type mice

• however, mutants do not exhibit spontaneous stereotypic behavior such as jumping, circling, paw flapping or self-grooming

• in the hot plate test, mutants exhibit shorter latency to respond to thermal stimuli indicating sensory hypersensitivity

• mutants exhibit reduced nest-building activity

• in a separation-reunion test with siblings, mutants show less interactions with siblings after reunion

• in the resident-intruder test, while wild-type mice explore the intruder extensively, mutants seldom chase the intruder and instead frequently show behaviors of avoidance, such as freezing and moving away

• in the social dominance tube test, mutants almost always retreat out of the tube and lose

• ultrasonic vocalization emitted by mutants is reduced significantly in terms of number, duration, and amplitude of calls in response to female odor compared to wild-type mice

• complexity of ultrasonic vocalization is reduced compared to wild-type mice

• in the hot plate test, mutants exhibit shorter latency to respond to thermal stimuli indicating sensory hypersensitivity

• excitatory synaptic transmission is altered in amygdala neurons

• however, mutants do not exhibit overt abnormalities in the overall morphology of the amygdala or in the morphology of dendritic arbors and spines in pyramidal neurons of the basolateral amygdala

• mutants exhibit depressed input-output curve of compound excitatory postsynaptic currents (EPSCs) in the basolateral amygdala

• mutants exhibit reduced AMPA receptor-mediated synaptic strength in basolateral amygdala neurons

• frequency of mEPSCs is reduced in mutant basolateral amygdala pyramidal neurons

• amplitude of mEPSCs is reduced in basolateral amygdala neurons, indicating that AMPA receptor-mediated postsynaptic activity is reduced

• however, neither the rising nor the decay of time of mEPSCs is altered, indicating that channel kinetics of AMPA receptors is preserved

• mutants exhibit reduced sensitivity to the motor stimulant effect of amphetamine and phencyclidine compared to control mice; the effect of amphetamine is delayed in the mutant while the response to phencyclidine is strongly attenuated compared to control

• mutant mice show enhanced acquisition of active avoidance with an augmented latent inhibition effect in the testing paradigm used

• mutants show enhanced expression of conditioned taste-aversion with an augmented latent inhibition effect in the testing paradigm used

• mutants exhibit and ehanced expression of conditioned tone-freezing with an augemented latent inhibition effect in the testing paradigm used

• augmented latent inhibition in conditioned freezing, conditioned active avoidance, and conditioned taste aversion tests

• in conditional mutants at P21-30, a 2.15-fold enhancement of the NMDA/AMPA response ratio compared to control is measured in brain slices