Figure 6.

Effects of [Ca²⁺]_o on dynamics of MPP synaptic variables during 50 Hz stimulation at two different pressures. (A) High [Ca²⁺]_o significantly increases P₁, but it significantly reduces the P_3-5 with respect to their respective controls. (B) At 10.1 MPa high [Ca²⁺]_o also increases P₁ at expenses of P_2–5 denoting reduction of E_T. Graphs display means ± SE, n = 6 for each condition *p < 0.05 and **p < 0.01 (paired t-test). (C) Differential effects of [Ca²⁺]_o and pressure on the dynamics of MPP synaptic variables. All the fractions were normalized with respect to E_T at control pressure and 4 mM [Ca²⁺]_o, (E_T’). The effect of [Ca²⁺]_o and pressure on sequential Ps: P_1–2 display significant difference between 0.1 MPa and 10.1 MPa in control [Ca²⁺]_o (n = 6, **p < 0.01). At high [Ca²⁺]_o all Ps were significantly depressed by 10.1 MPa (n = 6, ♦p < 0.05 for all of them). SE bars have been omitted for the sake of clarity.