[Background]
We have previously shown that bovine adrenocortical fasciculata cells (BAFC) expressed multiple P1 and P2 purinergic receptors (PRs), some of which are associated with enhancing ACTH-induced glucocorticoid production (GP) in BAFC. However, differences were noted in the protein expression profile of the PR subtypes depending on the individual BAFC.
[Objectives]
Therefore, we looked at whether the type of cell stimulation affects the mRNA expression of PRs in the BAFC.
[Materials & Methods]
BAFC were aseptically isolated from fresh bovine adrenal cortex and were cultured in Ham‘s F-10 medium supplemented with serum and antibiotics. Three-day primary cultured cells were used in all experiments. The cDNA of BAFC was constructed from total RNA and used for the qPCR templates.
[Results]
Stimulation of BAFC with A23187 (2 μM), a Ca²⁺ ionophore, significantly increased the expression of PRs more than 10-fold. Conversely, in cells stimulated with dibutyl cAMP (500 µM), a cell-permeable cAMP analog, PRs expression was suppressed less than 50%.
[Discussion]
In BAFC, it is well known that both continuous Ca²⁺ mobilization and cAMP accumulation induce GP. In the present study, however, cAMP accumulation reduced GP by suppressing the expression of PRs, which is involved in the promotion of GP.
[Conclusion]
Accumulation of cAMP in BAFC cells reduces the expression of PRs, preventing their overexpression. This suppression may be an aid in maintaining homeostasis.