FIGURE 7.

Peptidomimetic PAR₂ agonists induce Ca²⁺ signaling in primary cultures of trigeminal neurons. Trigeminal ganglia were excised, enzymatically dissociated, and plated onto glass coverslips. The following day changes in [Ca²⁺]_i in response to PAR₂ agonists (25 μm) were monitored for 7 min. 2-f-LIGRLO-NH₂ (A), 2-at-LIGRL-NH₂ (B), or 6-an-LIGRL-NH₂ (C) was applied to neurons and stimulated a rapid increase in [Ca²⁺]_i. A wash with HBSS was followed with a modified HBSS (37 mm K⁺) wash to identify trigeminal neurons within the cultures. Representative experiments (n = 8) are shown. [Ca²⁺]_i traces over time represent individual cells responding in the field of view.