Phenotypes for Hdc MGI:3620632 MGI Mouse

behavior/neurological phenotype ( J:220412 )

N	• mice show normal baseline locomotion, exploratory rearing, and center occupancy in the open field, and no evident spontaneous motor stereotypies or altered anxiety in the elevated plus maze or in the open field

abnormal behavioral response to amphetamine ( J:220412 )

• locomotor activation is attenuated after amphetamine administration and mutants become immobile after a high dose of amphetamine

• mutants show increased motor stereotypies compared to controls after amphetamine administration, consisting of repetitive focused sniffing and orofacial movements

• pretreatment with haloperidol, a dopamine D2 receptor antagonist, attenuates the stereotypies induced by amphetamine

• mice infused with histamine intracerebroventricularly immediately before administration of amphetamine show delayed and reduced amplitude of stereotypy

increased chemical nociceptive threshold ( J:106399 )

• mutants exhibit less paw-licking behavior (correlated with lowered pain sensitivity) in mutants compared with wild-type in response to subcutaneous injection of capsaicin or formalin

• intrathecal injection of histamine shortened the latency of the tail-flick test in null mice compared to wild-type; i.t. injection of a tachykinin NK1 receptor antagonist significantly inhibited histamine-related nociceptive behaviors in null mice

abnormal mechanical nociception ( J:106399 )

• the latency to respond to tail pressure is significantly longer in mutants compared to wild-type

increased thermal nociceptive threshold ( J:106399 )

• in hot-late, tail-flick and paw-withdrawal tests, the latency to respond to thermal stimuli is significantly prolongedin mutants compared to wild-type

increased dopamine level ( J:220412 )

• increase in striatal dopamine concentrations during the dark phase

• histamine infusion reduces levels of striatal dopamine

abnormal mast cell morphology ( J:70702 )

• mutant mast cells show pale and sparse granules compared to wild-type cells when stained with toluidine blue

decreased mast cell number ( J:70702 )

• numbers of mast cells in examined mesenterial membrane preparations from mutants are decreased by 55% compared to wild-type; numbers of mast cells in mutants are decreased in peritoneal cell suspensions as well

decreased mast cell histamine storage ( J:70702 )

• tissue histamine levels is almost zero in various organs except for the brain; mast cells in mutants have reduced granular content

decreased mast cell protease storage ( J:70702 )

• the amount of granular protease in mast cells is decreased in mutants

abnormal substantia nigra morphology ( J:220412 )

• mice exhibit higher dopamine D2 and D3 receptor density in the substantia nigra than controls

abnormal striatum morphology ( J:220412 )

• striatal histamine concentrations are reduced

• mice exhibit a reduction in dopamine D2 and D3 receptor density in the dorsal striatum

decreased prepulse inhibition ( J:220412 )

• mice exhibit a deficit in auditory PPI at three prepulse intensities