Temporal Relationships Among Testosterone Production, Steroidogenic Acute Regulatory Protein (StAR), and P450 Side‐Chain Cleavage Enzyme (P450scc) During Leydig Cell Aging is a research paper published in Journal of Andrology (2005). On theSindex it has a DataRank of 3.2. It has been cited 80 times, with 70 citing works in its 1-hop citation network.
ABSTRACT: Previous studies have shown that the capacity of Leydig cells from aged (21‐24‐month‐old) Brown Norway rats to produce testosterone is reduced from young (4‐month‐old) levels, and that this is correlated with reductions in steroidogenic acute regulatory protein (StAR), peripheral benzodiazapine receptor (PBR), and the levels and activities of the steroidogenic enzymes. The age(s) at which particular changes in the steroidogenic pathway occur, and the relationship of particular changes to reduced testosterone production, are not known. We examined 3 critical components of the steroidogenic pathway, cyclic adenosine monophosphate (cAMP) production, StAR, and P450 side‐chain cleavage enzyme (P450scc) in relationship to age‐related decreases in testosterone production. Leydig cells isolated from Brown Norway rats of increasing ages (4, 9, 15, and 20 months) were evaluated. The ability of Leydig cells to produce testosterone was reduced at 9 months, although not significantly. Significant reductions in testosterone production were first seen in cells isolated from rats of 15 months of age, and further reductions occurred thereafter. Reduced testosterone was correlated with reductions in StAR, P450scc mRNA, and protein. Significant decline in luteinizing hormone‐stimulated intracellular cAMP levels was seen by 9 months, before significant reductions in testosterone, StAR, and P450scc. Further declines in cAMP levels were seen at 15 and 20 months. These studies suggest that age‐related reductions in intracellular cAMP may lead to the reduced testosterone production that characterizes aged Leydig cells. This suggestion is supported by recent studies from our lab demonstrating that long‐term (3 days) culture of old Leydig cells with dbcAMP restored testosterone production to levels approximating those of young cells.
FAIR checklist signals are shown for context only and do not affect DataRank scoring.
Base Score Contribution
0.659
From this paper's citation signal
Citation Network Contribution
2.5
From 65 citing papers with measurable signal
Ranked by citation count — the same ordering the engine uses when summing log1p(Cq) over citers.
DataRank blends this paper's own citation count with the influence of the papers that cite it. Here, roughly 21% comes from its base citations and 79% from the citation network (65 citing papers contributed measurable signal).
Citers are pulled from OpenAlex sorted by cited_by_count:descand capped per paper, so when the cap binds we keep the highest-signal references and the score is reproducible across reruns.
Click a node to highlight its connections. Use scroll to zoom. Drag to pan.