A mechanism underlying gender‐related differences in pain perception may be estrogen modulation of nociceptive signaling in the peripheral nervous system. In rat, dorsal root ganglion (DRG) neurons express estrogen receptors (ERs) and estrogen rapidly attenuates ATP‐induced Ca²⁺ signaling. To determine which estrogen receptor mediates rapid actions of estrogen, we showed ERα and ERβ expression in DRG neurons from wild‐type (WT) female mice by RT‐PCR. To study whether ERα or ERβ mediates this response, we compared estradiol action mediating Ca²⁺ signaling in DRG neurons from WT, ERα knockout (ERαKO), and ERβKO mice in vitro. ATP, an algesic agent, induced [Ca²⁺]_i transients in 48% of small DRG neurons from WT mice. 17β‐Estradiol (E₂) inhibited ATP‐induced intracellular Ca²⁺ concentration ([Ca²⁺]_i) with an IC₅₀ of 27 nM. The effect of E₂ was rapid (5‐min exposure) and stereo specific; 17α‐estradiol had no effect. E₂ action was blocked by the ER antagonist ICI 182,780 (1 μM) in WT mouse. Estradiol coupled to bovine serum albumin (E‐6‐BSA), which does not penetrate the plasma membrane, had the same effect as E₂ did, suggesting that a membrane‐associated ER mediated the response. In DRG neurons from ERβKO mice, E₂ attenuated the ATP‐induced [Ca²⁺]_i flux as it did in WT mice, but in DRG neurons from ERαKO mice, E₂ failed to inhibit the ATP‐induced [Ca²⁺]_i increase. These results show that mouse DRG neurons express ERs and the rapid attenuation of ATP‐induced [Ca²⁺]_i signaling is mediated by membrane‐associated ERα. © 2005 Wiley‐Liss, Inc.