AVD
The Mind of 
	a Worm

Members: AVDL, AVDR.

AVD is a pair of interneurons with cell bodies situated in the lateral ganglia. Anteriorly directed processes leave the cell bodies and enter the ring sub-dorsally, where they initially run near the inside surface of the neuropile. They move out near the outside surface as the processes cross over on the dorsal mid-line (e) and move back to the middle of the neuropile as they carry on round the ring. They then enter the ventral cord where they run near the middle of the process bundle (figure 18), eventually ending in the pre-anal ganglion. The processes of AVD are exclusively postsynaptic in the nerve ring and are lightly staining. The main synaptic input in this region is from ASH (*c), ADL (*d), FLP (*b), PVC (*c) and AQR. There are gap junctions to ADA (*d) and FLP. AVD is predominantly presynaptic in the ventral cord having the same post-synaptic partners as AVE. It makes many synapses to AVA (a, b, c, d) and several to SAB (f, g), VAn (a), DAn (c) and ASn (d), usually in various dyadic combinations. There are some striking synaptic complexes in the vicinity of the cell bodies of the SAB neurons, where two presynaptic specializations from AVD and/or AVE (and sometimes also AVA) occur in the same region with the processes of SAB, DA1 and VA1 sandwiched in between (f). The main synaptic input to AVD in the ventral cord is from PQR (*g), LUA (*a), PVN (*b) and PLM (*f), there are also minor inputs from AVB (*b), PHB (*c) and possibly PVW (*c). There are gap junctions to AVJ, AVM (*e) and FLP in the cord. Magnifications: (a) x 25500, (b-d, f, g) x 17000, (e) x 12750.


AVD ventral cord synapses
partners gap junctions synapses from synapses to and corecipients
AVA - 2 7, 33AVA, 4SABV, 3DA1, 3LUA, 2DA4, 2AS11, 2SABD, 2AVD, VA6, DA5, PVC, AS4, ASIO, VA5, VA11, DA8, PQR, VA3, DB4, DA3
DA3 - - 5,AVA
SABV - - 4 AVA, 2SABV
DA4 - - 2, 2AVA
LUA - 7m 3 AVA
SABD - - 1, 2AVA
DA1 - - 3AVA
DA5 - - 2,AVA
VA3 - - 2,AVA
AS11 - - 2AVA
AVD - - 2AVA
DA2 - - 2
VA6 - - 1,AVA
ASIO - - 1,AVA
PQR - 12 m AVA
PVN - 6m -
DA8 - - AVA
PVC - 3m AVA
AS1 - - 1
AS4 - - AVA
AVB - 3m 1
DA9 - - 1
VA2 - - 1
DVC - - 1
AS5 - - 1
DB4 - - AVA
VA11 - - AVA
VA5 - - AVA
FLP - 2 + 18m -
PLM - 1+4m -
AVJ 4 4m -
PHB - 3m -
HSN - 3m -
AVG - 1 -
VA4 - 1 -
PHA - 1m -
PVW - 1m -
AVE - 1m -
AVM 1 - -


Web adaptation, Thomas Boulin, for Wormatlas, 2001, 2002