Effects of forskolin on the longitudinal internal resistance (ri)in rabbit sinus node strips

Tuganowski, W., Korczyńska, I., Wąsik, K., Wójcik В. and Bukowski, M.; Effects of forskolin on the longitudinal internal resistance (ri) in rabbit sinus node strips. Aclta physiol. pod., 1989, 40 (2): 164-170. The effect of several concentrations of 7-0-hemisucoinyl, 7-deacetyl forskolin on n was studied by means of microelectrode and single sucrose gap techniques. Twenity µmol·1⁻¹ of forskolin added ifco to the sucrose gap lowered ri 15% below the control value. The drug applied at 50 µmol·l⁻¹ initially decreased ri by 31%, and then it increased the resistance by 43% above the control, value. The possible mechanisms underlying these effects are discussed in terms of cAMP and Ca action on the cell coupling.