The neurotrophin NGF increases cold sensitivity of cultured rat DRG neurones, primarily through an effect on cold- and menthol-sensitive cells (Reid et al. 2002; Babes et al. 2004). Two NGF receptors with different affinities for NGF have been characterised so far: the low affinity receptor (Kd = 1 nM) identified as the non-specific neurotrophin receptor p75, and the high affinity receptor (Kd = 10 pM), composed of both p75 and the tyrosine kinase NGF receptor trkA (Mahadeo et al. 1994). The aim of this work was to identify which of the two receptors is involved in sensitising DRG neurones to cold. Wistar rats were humanely killed. Primary DRG cultures were split in four groups and 7S NGF was added to the four fractions as follows: no NGF (control), 1 ng/ml (7.7 pM), 10 ng/ml (77 pM) and 200 ng/ml (1.5 nM). Cells were stimulated by cooling from 32 to 17 °C with a Peltier based temperature controlled application system, and changes in [Ca²⁺]_i were monitored using Calcium Green-1 fluorimetry (Reid et al., 2002). The following parameters were measured: fraction of menthol-sensitive (MS) neurones, amplitude and temperature threshold of the cold response, and sensitivity to capsaicin (CAP) and cinnamon aldehyde (CA). Data are presented as mean ± SD. χ² test and Student′s t test were used to determine statistical significance. NGF increased the fraction of MS cells in days 2 and 3 after the culture (14.3% for 7.7 pM NGF compared to 4.5% for control, in day 2, p < 0.001). The effect was significant for all three NGF concentrations tested in day 2 and for the two higher concentrations in day 3. The amplitudes of the calcium signals induced by cooling were not different in the four groups, but the threshold temperatures were significantly different from control for all three groups with added NGF (28.4 ± 2.7 °C for 7.7 pM NGF, n = 31, compared to 25.3 ± 3.5 °C for control, n = 19, p = 0.001). CAP sensitivity of MS neurones was increased by 77 pM NGF from 57% to 80% while, interestingly, co-expression of menthol and CA sensitivity was significantly decreased by addition of 77 pM NGF, from 58% to 39% (p = 0.01). We conclude that the sensitising effects of NGF on MS neurones in rat DRG cultures and the degree of co-expression with CAP and CA sensitivities are all mediated primarily by the high affinity NGF receptor.