AVB is a pair or interneurons with cell bodies situated in the lateral ganglia. Processes leave the cell bodies and enter the ventral cord via the amphidial commissures (h). They then turn, run anteriorly into the nerve ring and run right round it near the middle of the neuropile, in close association with the processes of PVC and AVJ. They reenter the ventral nerve cord on the contralateral side and run along it in the dorsal region of the process bundle (figure 18), ending in the posterior body before the pre-anal ganglion is reached (i). AVB, together with AVA, are the most prominent interneurons of the ventral cord. The processes of AVB are large and lightly staining (e, f, g) and have several short projections emanating from them in the nerve ring (e, f). AVB is entirely postsynaptic in the nerve ring, where it receives many synaptic inputs. These come mainly from RIF (*b), RIM (*f), AVM (*a), PVC (*b), ASH (*b), PVR (*a), PVP (*a), SDQ (*a), ADA (*a), AQR (*a), FLP (*b), AIB (*c), AVF (*c), ADL and URX. There are also gap junctions to RIB (*g), SIBV (*d), DVA (*g), RID (*c), SDQ and itself (g) in the nerve ring. AVB is predominantly presynaptic in the ventral cord, where it synapses mainly onto AVA (b), ASn (c) and the hypodermis (HDC) (a) together with a few small synapses onto AVD (d) and AVE (d). There are gap junctions to all the VBn (*c) and DBn (*c) motoneurons, usually in the vicinity of their cell bodies. AVB has little synaptic input in the ventral cord; what there is comes from AVF (*c), PVN (*c) and PVC. Magnifications: (a, f, g) x 25500, (b-d) x 17000, (e) x 12750.
|partners||gap junctions||synapses from||synapses to and corecipients|
|AVA||-||1+1m||21, 2AVA, DA5, AVD|
|AVD||-||-||AVA, AVB, AVE|
|AVE||-||-||1, AVD, VA4|
|AVB||-||2m||VD3, A VD|
Web adaptation, Thomas Boulin, for Wormatlas, 2001, 2002