ISSN:
0730-2312
Keywords:
steriod hormone
;
vitamin D hormone
;
nongenomic actions
;
osteoblasts
;
membrane receptor
;
Life and Medical Sciences
;
Cell & Developmental Biology
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Biology
,
Chemistry and Pharmacology
,
Medicine
Notes:
Recent studies indicate that the vitamin D hormone, 1α,25-Dohydroxyvitamin D3 exerts rapid effects (seconds to minutes) in a variety of cell types. These rapid nongenomic actions in osteoblasts include effects on membrance voltage-gated calcium chananels, phosphlipase C activity, and the sodium/dydrogen antiport. Since the rapid effects occur in osteoblasts that lack the neclear vitamin D receptor, it is postulated that the nongenomic responses to the hormone reflect interaction with a separate, membrane localized signalling system. Preliminary studies demonstrate the presence of a receptor on the membranes of osteoblasts that lack the neclear vitamin D. This membranes receptors recognizes 1 a, 25-dihyrooxyvitamin D3 and its inaction 1β epimer, but not 25-hydrovitamin D3. These rapid nongenomic actions generated by interaction with the membrane receptor modulate the effect of the hormone on gene transcription. Thus, the rapid nongenomic pathway may play a regulatory function in modulating the genomic pathways affected by 1 a 25-dihydroxyvitamin D3.
Additional Material:
1 Tab.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/jcb.240560305
