Table 1.
Summary of increases in cytosolic calcium concentration of afferent arterioles in response to high extracellular KCl and pharmacological agents
| Peak [Ca2+]i |
Plateau [Ca2+]i |
|||||
|---|---|---|---|---|---|---|
| Group | Mean ± SE | P* | P† | Mean ± SE | P* | P† |
| KCl | 151±3 (28) | 101±2 | ||||
| KCl + l-NAME | 126±21 (6) | NS | 97±20 | NS | ||
| KCl + ODQ | 124±15 (4) | NS | 90±16 | NS | ||
| KCl + KT-5823 | 105±10 (5) | NS | 77±8 | NS | ||
| KCl + IBX | 134±2 (5) | NS | 108±4 | NS | ||
| KCl + SNP | 77±8 (12) | <0.001 | 60±8 | <0.001 | ||
| KCl + SNP + IBX | 126±18 (10) | NS | <0.05 | 86±10 | NS | NS |
| KCl + SNP + KT-5823 | 54±1 (9) | <0.01 | NS | 45±1 | <0.001 | NS |
| KCl + SNP + IBX + KT-5823 | 75±3 (9) | <0.001 | NS | 60±2 | <0.001 | NS |
| KCl + SNP + ODQ | 66±6 (5) | <0.01 | NS | 47±5 | <0.001 | NS |
| KCl + SNP +8-Br-cADPR | 81±3 (11) | <0.01 | NS | 75±4 | NS | NS |
| KCl +8-Br-cGMP | 143±8 (9) | NS | 109±8 | NS | ||
| KCl +8-Br-cGMP + IBX | 340±27 (9) | <0.001 | 137±7 | <0.001 | ||
Values are means ± SE for no. of observations in parentheses. [Ca2+]i, cytosolic calcium concentration; l-NAME, Nω-nitro-l-arginine methyl ester; ODQ, 1,2,4-oxodiazolo-[4,3-a]quinoxalin-1-one; IBX, iberiotoxin; SNP, sodium nitroprusside; 8-Br-cADPR, 8-bromo-cyclic adenosine diphosphoribose; 8-Br-cGMP, 8-bromoguanosine 3′,5′-cyclic monophosphate.
*
P vs. KCl: ANOVA for “peak” P < 0.001, ANOVA for “plateau” P < 0.001;
†
P vs. KCl + SNP: ANOVA for “peak” P < 0.001, ANOVA for “plateau” P < 0.001; NS, not significant (P > 0.05).