Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: EC:3.4.24.3 (
collagenase
)
18,340
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
We measured phosphatidylcholine secretion and its response to surfactant secretagogues in type II cells from developing rats. Cells were isolated from fetal rats on day 21 of gestation by digestion with
collagenase
and trypsin and purification by differential adhesion. Cells were isolated from adult and postnatal rats on days 1, 7, 14, and 30 by elastase digestion and panning on immunoglobulin G-coated dishes. The basal rate of phosphatidylcholine secretion was the same at all ages but there were developmental changes in the response to secretagogues. The response to terbutaline and an adenosine A2 receptor agonist increased from fetal life until day 7 when it reached the level of adult cells.
Adenosine deaminase
did not increase the response of the cells to these agonists until day 30, suggesting that the adenosine A1 receptor inhibiting secretion does not become functional until that age. The response to 12-O-tetradecanoylphorbol 13-acetate was lower in the fetal cells but had reached the adult level by day 1. The developmental increase in the response of the cells to ATP was more prolonged with the maximum response not being attained until day 30. With the exception of day 30, when the response to most of the secretagogues was very high, the response to ionomycin was the same at the other ages. These data suggest differential maturation of the signal-transduction pathways mediating surfactant secretion in type II cells.
...
PMID:Ontogeny of surfactant secretion in type II pneumocytes from fetal, newborn, and adult rats. 155 Feb 57