Time of culture and cell collection. Granulosa cells can be cul-tured for up to 48 h whilst preserving their endocrine activity and LH responsiveness, however, P4 production in the first 24 h of cul-ture was significantly greater (Fig. 3, panel A). Furthermore, when T and LH were added to the culture, no interaction with time of culture was observed (Fig. 3, panels B and C) (Rangel et al.,