Two forms of sensitization of the local bending reflex of the medicinal leech
- Cite this article as:
- Lockery, S.R. & Kristan, W.B. J Comp Physiol A (1991) 168: 165. doi:10.1007/BF00218409
Sensitization of local bending could be produced in two ways: by repeated stimulation of the mechanoreceptor sensitive to pressure (the P cell), and by stimutlation of the mechanoreceptor sensitive to noxious stimuli (the N cell).
Both forms of sensitization produced a central neuronal change, measured as an increase in the number of stimulus-evoked action potentials in cell 3 (an excitor of dorsal longitudinal muscles).
Intracellular stimulation of serotonin-containing neurons 21 and 61 mimicked the sensitizing stimuli, but stimulation of the Retzius cell, which also contains serotonin, did not.
Stimulation of the Leydig cell, which releases octopamine, decreased the strength of local bending.
Key wordsLeech Sensitization Neural correlates Serotonin
analysis of variance
dorsal posterior nerve