Sp-8-CPT-cAMPS is a powerful and specific cAMP analog that activates cAMP-dependent protein kinase A (PKA I and PKA II) selectively and effectively. It exhibits a 153-fold preference for site A of RI over site A of RII, and a 59-fold preference for site B of RII over site B of RI.

Sp-8-CPT-cAMPS at a concentration of 100 μM and duration of 24 hours notably amplifies IL-1β-induced nitrite release in vascular smooth muscle cells, augmenting this release threefold even without IL-1β presence. Additionally, it boosts the expression of iNOS protein in rat aortic smooth muscle cells under the same conditions [2]. At a lower concentration and shorter exposure (10 μM; 30 min), Sp-8-CPT-cAMPS demonstrates anti-spasmogenic properties by reducing acetylcholine (ACh)-induced tension in guinea-pig trachealis [3].