Expression and alteration of BK_Ca channels in the sphincter of Oddi's from rabbits with hypercholesterolemia

Figures & data

Figure 1. The serum cholesterol levels (A) and body weight (B) of the rabbits in the control and HC groups. n = 18. **p < 0.01, HC vs control.

Figure 2. BK_Ca channel currents recorded on SOSMCS in rabbits from the control and HC groups. (A) Representative potassium currents recorded in SOSMCs from control group in the presence or absence of 10 μM paxilline. (B) BK_Ca currents recorded in primarily cultured SOSMCs from rabbits in the control group and HC group (the voltage protocol shown above). (C) I-V relationships of BK_Ca current density in SOSMCs from the control group (n = 8) and HC group (n = 8). *p < 0.05, ** p < 0.01.

Figure 3. The protein expression of BK_Ca channels in SOSMCs in the control and HC groups. (A) Representative immunohistochemically staining of α-SMC, BK_Ca α- subunits, and BK_Ca β₁-subunits in SOSMCs. Magnification, ×200. (B) Western blot analysis showing the total protein expression of BK_Ca α-. and β₁-.subunits. (C) The protein expression of Tyr-phosphorylated BK_Ca α-. and β₁-.subunits. The proteins were immunoprecipitated with antibodies against phosphorylated BK_Ca α- and β₁-subunits and detected with Western blot. CON: SOSMCs from control group rabbits; HC: SOSMCs from hypercholesterolemia group rabbits; Microglial cells used for negative control. n = 5. **p < 0.01, HC vs control.

Figure 4. Effects of NS1619, Na₃VO₄, and Genistein on ACh-induced contraction of the SO rings in HC rabbits. (A) The concentration-response curve of ACh-induced contraction of the SO rings in the control, HC and HC+NS1619 groups. SO rings were pretreated with NS1619 (30 μM) for 15minutes. (B) The concentration-response curve of ACh-induced contraction of the SO rings in the HC, HC + Na₃VO₄, and HC + Genistein groups. SO rings were pretreated with Na₃VO₄ (100 μM) for 30 min, or Genistein (10 μM) for 30 min. (C) The concentration-response curve of ACh-induced contraction of the SO rings in the HC, HC + Na₃VO₄, HC + NS1619, and HC + Na₃VO₄ + NS1619 groups. SO rings were pretreated with Na₃VO₄ (100 μM) for 30 min, or/and NS1619 (30 μM) for 30 min. n = 8. *p < 0.05, # p < 0.01.