Effects of ruthenium red, A23187 and D-600 on steroidogenesis in Y-1 cells

Area of Science:

• Endocrinology
• Cell Biology
• Biochemistry

Background:

• Steroidogenesis is a critical process regulated by calcium ions.
• The precise role of intracellular calcium in steroidogenesis requires further elucidation.

Purpose of the Study:

• To investigate the effects of calcium antagonists (ruthenium red, D-600) and a cation ionophore (A23187) on steroidogenesis in Y-1 cells.
• To determine whether these agents act by altering intracellular calcium levels.

Main Methods:

• Steroidogenesis was induced using corticotrophin and cyclic adenosine monophosphate (cAMP).
• The impact of calcium antagonists and ionophore on steroidogenesis was assessed.
• Ethyleneglycol-bis-(beta-amino-ethylether)-N,N'-tetraacetic acid (EGTA) was used to chelate extracellular calcium.
• Responses to exogenous pregnenolone were measured to assess cell viability.

Main Results:

• Ruthenium red, D-600, and A23187 inhibited steroidogenesis induced by both corticotrophin and cAMP.
• The inhibition of cAMP-induced steroidogenesis (independent of extracellular calcium) suggests intracellular calcium involvement.
• Cell viability was maintained, as evidenced by unaffected responses to exogenous pregnenolone, except when A23187 was combined with high extracellular calcium.

Conclusions:

• Intracellular calcium plays a significant role in the steroidogenic pathway in intact cells.
• Calcium antagonists and ionophores can modulate steroidogenesis by influencing intracellular calcium dynamics.
• These findings provide further evidence for the importance of intracellular calcium regulation in steroid hormone production.