Abstract
Hypoxic vasoconstriction (HV) is an intrinsic response of mammalian pulmonary and cyclostome aortic vascular smooth muscle. The present study examined the utilization of calcium during HV in dorsal aortas (DA) from sea lamprey and New Zealand hagfish. HV was temporally correlated with increased free cytosolic calcium (Ca 2+ ) in lamprey DA. Extracellular calcium (Ca o 2+ ) did not contribute significantly to HV in lamprey DA, but it accounted for 38.1 ± 5.3% of HV in hagfish DA, Treatment of lamprey DA with ionomycin, ryanodine, or caffeine added to thapsigargin-reduced HV, whereas HV was augmented by BAY K 8644. Methoxyverapamil (D600) in zero Ca o 2+ did not affect HV in lamprey DA, nor did it prevent further constriction when Ca 2+ was restored during hypoxia in hagfish DA. Removal of extracellular sodium (Na o + ) caused a constriction in both species. Lamprey DA relaxed to prehypoxic tension following return to normoxia in zero Na o + , whereas relaxation was inhibited in hagfish DA. Relaxation following HV was inhibited in lamprey DA when Na o + and Ca o 2+ were removed. These results show that HV is correlated with [Ca 2+ ] c in lamprey DA and that Na + /Ca 2+ exchange is used during HV in hagfish but not lamprey DA. Multiple receptor types appear to mediate stored intracellular calcium release in lamprey DA, and L-type calcium channels do not contribute significantly to constriction in either cyclostome.
| Original language | English (US) |
|---|---|
| Journal | American Journal of Physiology - Regulatory Integrative and Comparative Physiology |
| Volume | 281 |
| Issue number | 5 50-5 |
| State | Published - Dec 17 2001 |
| Externally published | Yes |
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Keywords
- Hagfish
- Lamprey
- Vascular smooth muscle
ASJC Scopus subject areas
- Physiology
- Physiology (medical)
Cite this
Intracellular and extracellular calcium utilization during hypoxic vasoconstriction of cyclostome aortas. / Russell, Michael James; Pelaez, N. J.; Packer, C. S.; Forster, M. E.; Olson, K. R.
In: American Journal of Physiology - Regulatory Integrative and Comparative Physiology, Vol. 281, No. 5 50-5, 17.12.2001.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Intracellular and extracellular calcium utilization during hypoxic vasoconstriction of cyclostome aortas
AU - Russell, Michael James
AU - Pelaez, N. J.
AU - Packer, C. S.
AU - Forster, M. E.
AU - Olson, K. R.
PY - 2001/12/17
Y1 - 2001/12/17
N2 - Hypoxic vasoconstriction (HV) is an intrinsic response of mammalian pulmonary and cyclostome aortic vascular smooth muscle. The present study examined the utilization of calcium during HV in dorsal aortas (DA) from sea lamprey and New Zealand hagfish. HV was temporally correlated with increased free cytosolic calcium (Ca 2+ ) in lamprey DA. Extracellular calcium (Ca o 2+ ) did not contribute significantly to HV in lamprey DA, but it accounted for 38.1 ± 5.3% of HV in hagfish DA, Treatment of lamprey DA with ionomycin, ryanodine, or caffeine added to thapsigargin-reduced HV, whereas HV was augmented by BAY K 8644. Methoxyverapamil (D600) in zero Ca o 2+ did not affect HV in lamprey DA, nor did it prevent further constriction when Ca 2+ was restored during hypoxia in hagfish DA. Removal of extracellular sodium (Na o + ) caused a constriction in both species. Lamprey DA relaxed to prehypoxic tension following return to normoxia in zero Na o + , whereas relaxation was inhibited in hagfish DA. Relaxation following HV was inhibited in lamprey DA when Na o + and Ca o 2+ were removed. These results show that HV is correlated with [Ca 2+ ] c in lamprey DA and that Na + /Ca 2+ exchange is used during HV in hagfish but not lamprey DA. Multiple receptor types appear to mediate stored intracellular calcium release in lamprey DA, and L-type calcium channels do not contribute significantly to constriction in either cyclostome.
AB - Hypoxic vasoconstriction (HV) is an intrinsic response of mammalian pulmonary and cyclostome aortic vascular smooth muscle. The present study examined the utilization of calcium during HV in dorsal aortas (DA) from sea lamprey and New Zealand hagfish. HV was temporally correlated with increased free cytosolic calcium (Ca 2+ ) in lamprey DA. Extracellular calcium (Ca o 2+ ) did not contribute significantly to HV in lamprey DA, but it accounted for 38.1 ± 5.3% of HV in hagfish DA, Treatment of lamprey DA with ionomycin, ryanodine, or caffeine added to thapsigargin-reduced HV, whereas HV was augmented by BAY K 8644. Methoxyverapamil (D600) in zero Ca o 2+ did not affect HV in lamprey DA, nor did it prevent further constriction when Ca 2+ was restored during hypoxia in hagfish DA. Removal of extracellular sodium (Na o + ) caused a constriction in both species. Lamprey DA relaxed to prehypoxic tension following return to normoxia in zero Na o + , whereas relaxation was inhibited in hagfish DA. Relaxation following HV was inhibited in lamprey DA when Na o + and Ca o 2+ were removed. These results show that HV is correlated with [Ca 2+ ] c in lamprey DA and that Na + /Ca 2+ exchange is used during HV in hagfish but not lamprey DA. Multiple receptor types appear to mediate stored intracellular calcium release in lamprey DA, and L-type calcium channels do not contribute significantly to constriction in either cyclostome.
KW - Hagfish
KW - Lamprey
KW - Vascular smooth muscle
UR - http://www.scopus.com/inward/record.url?scp=0035202748&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0035202748&partnerID=8YFLogxK
M3 - Article
VL - 281
JO - American Journal of Physiology - Heart and Circulatory Physiology
JF - American Journal of Physiology - Heart and Circulatory Physiology
SN - 0363-6135
IS - 5 50-5
ER -