Figure 6.

Fluid shear–induced calcium and transient NO require polaris and polycystin-1. A, Response of individual wild-type (wt), Pkd1^null/null (Pkd1), and Tg737^orpk/orpk (Tg737) cells from static condition to fluid shear stress of 7.2 dynes/cm² is pseudocolored. The calcium (red) and NO (green) are superimposed. The color bar indicates the calcium (Ca²⁺) or NO level relative to the corresponding baseline level. Black and blue represent a low (lo) level; red and green denote a higher (hi) level of calcium and NO, respectively. B, The average cytosolic calcium ([Ca²⁺]_cyt) response to shear stress. C, The average cytosolic NO ([NO]_cyt) response. Fluid shear stress was applied after the baseline values of calcium and NO were obtained for at least 14 seconds as indicated by arrows. All the units of time are seconds. n = 5. *Statistically significant responses from the baseline values.